@prefix vivo: . @prefix edm: . @prefix dcterms: . @prefix dc: . @prefix skos: . @prefix ns0: . vivo:departmentOrSchool "Environmental Health (SOEH), School of"@en, "Occupational and Environmental Hygiene, School of"@en, "Medicine, Faculty of"@en, "Population and Public Health (SPPH), School of"@en ; edm:dataProvider "DSpace"@en ; dcterms:contributor "University of British Columbia. Centre for Health and Environment Research"@en ; dcterms:creator "Kennedy, Susan"@en, "Copes, Ray"@en, "Brauer, Michael"@en, "Na, Sonia"@en, "Karlen, Barbara"@en, "Leung, Victor L. T."@en ; dcterms:issued "2008-06-09T18:30:03Z"@en, "2001-08-07"@en ; dcterms:description "An investigation into workplace exposures linked to the use of glass breaking machinery in BC liquor stores and their possible impact on employee health."@en ; edm:aggregatedCHO "https://circle.library.ubc.ca/rest/handle/2429/882?expand=metadata"@en ; dcterms:extent "14814 bytes"@en, "290535 bytes"@en, "100918 bytes"@en, "28196 bytes"@en, "26380 bytes"@en, "26761 bytes"@en ; dc:format "application/pdf"@en ; skos:note " Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 4, Page 1 of 4 UBC School of Occupational and Environmental Hygiene Bioaerosols, Airborne Particulate Matter and Symptoms in BC Liquor Distribution Branch Stores Susan Kennedy, Ray Copes, Michael Brauer, Sonia Na, Barbara Karlen, Victor Leung August 7, 2001 Appendix 4: Exposures, by individual visit and store, region Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 4, Page 2 of 4 Appendix 4: Exposures, by individual visit and store, region Figure 1: Average dust levels, by store and visit GVRD/Lower Mainland mean dust, by store/visit White/black pairs indicate shut-down sites; Visit 1=left, Visit 2=right 0.0 100.0 200.0 300.0 400.0 6 25 38 58 71 98 117 152 163 205 237 7 11 70 87 90 121 200 208 Site # IP M c on c, µ µµµ g/ m 3 Victoria & area mean dust by store/visit White/black pairs indicate shut-down sites; Visit 1=left, Visit 2=right 0.0 100.0 200.0 300.0 400.0 12 68 140 161 178 59 150 173 204 206 218 242 Site # IP M c on c, µ µµµ g/ m 3 Remote/ Interior mean dust by store/visit White/black pairs indicate shut-down sites; Visit 1=left, Visit 2=right 0.0 100.0 200.0 300.0 400.0 78 126 188 21 63 Site # IP M c on c, µ µµµ g/ m 3 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 4, Page 3 of 4 Figure 2: Average endotoxin levels, by store and visit GVRD/ Lower M ainland m ean endotoxin by store & visit W hite/black pairs indicate shut-down sites; Visit 1= Left bar, Visit 2= Right bar 0 1 2 3 4 6 25 38 58 71 98 117 152 163 205 237 7 11 70 87 90 121 200 208 Site # E n do to xi n co nc ( ng3 ) Victoria & Area m ean endotoxin by store & visit W hite/black pairs indicate shut-down sites; Visit 1= Left bar, Visit 2= Right bar 0 1 2 3 4 12 68 140 161 178 59 150 173 204 206 218 242 Site # E n do to xi n co nc ( ng3 ) Rem ote/ Interior m ean endotoxin, by store & visit W hite/black pairs = shut down sites; Visit 1= Left, Visit 2= Right 0 1 2 3 4 78 126 188 21 63 Site # E n do to xi n co nc ( ng3 ) Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 4, Page 4 of 4 Figure 3: Fungal counts (peak and average), by store, visit G VRD / Low er M ainland peak fungal counts by store & visit W hite/black pairs indicate shut-dow n sites; Visit 1= left bar, Visit 2= right bar 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000 6 25 38 58 71 98 117 152 163 205 237 7 11 70 87 90 121 200 208 Site # C o u n t (C FU /m 3 Bars=maximums; points=mean values Victoria & Area fungal counts W hite/black pairs indicate shut-down sites; Visit 1= left bar, Visit 2= right bar Bars= m axim um s; points= m eans 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000 12 68 140 161 178 59 150 173 204 206 218 242 Site # C o u n t (C FU /m3 ) Remote/Interior fungal counts White/black pairs indicate shut-down sites; Visit 1=left bar, Visit 2=right bar Bars=maximums; points=means 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000 78 126 188 21 63 Site # Co un t (C FU /m 3 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 3, Page 1 of 5 UBC School of Occupational and Environmental Hygiene Bioaerosols, Airborne Particulate Matter and Symptoms in BC Liquor Distribution Branch Stores Susan Kennedy, Ray Copes, Michael Brauer, Sonia Na, Barbara Karlen, Victor Leung August 7, 2001 Appendix 3 - Definitions used Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 3, Page 2 of 5 Appendix 3: Definitions of variables used in analyses Definitions arising from symptom questionnaires: Symptom 'name' detailed description Symptoms 1 Usual cough positive response to the question: do you usually have a cough (not including 'clearing your throat')? 2 Usual phlegm positive response to the question: do you usually bring up phlegm from your chest (not from your nose)? 3 Wheeze occasionally, apart from colds positive response to the question: Does your chest ever sound wheezy or whistling, occasionally apart from colds? 4 Wheezing with breathlessness Positive response to Q 3 above, plus positive response to: Is the wheeze associated with chest tightness or difficulty breathing? 5 Chest tightness episodes Positive response to the question: Do you ever have episodes or attacks of chest tightness? 6 Shortness of breath hurrying on the level Positive response to the question: Are you troubled by shortness of breath when hurrying on the level or walking up a slight hill? 7 Shortness of breath walking on the level Positive response to Q 6 above, plus: positive response to: Do you have to walk slower than people of your own age, on the level, because of breathlessness? 8 Sneezing, itching, running nose Positive response to the question: Do you ever have sneezing, or an itchy, runny nose when you do not have a cold? 9 Eye symptoms Positive response to the question: Do you usually have burning, itching, watering eyes? 10 Work-related ________ (each of the above) Positive response to the symptom Q, plus: age symptom first appeared greater than age first started with current employer; and one or both of: symptom is aggravated by environmental agents at work symptom improves on weekends or long holidays 11 Acute symptoms (see list in report for specific symptoms) Positive response to the question: in the past week have you experienced (symptom name), plus - when asked 'how often?' - responds more than once, and - when asked 'how much did it bother you?', responds 'some' or 'very much' 13 nose / throat irritation two or more of the following acute symptoms (as defined in Q 11 above): irritated nose, throat, voice, or taste disturbances 14 chest symptoms two or more of the following acute symptoms (as defined in Q 11 above): dry cough, chest tightness, wheezing, breathlessness 15 somatic symptoms two or more of the following acute symptoms (as defined in Q 11 above): fever, headache, dizziness, tiredness, nausea Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 3, Page 3 of 5 Demographics and health history 16 Current smoker Smoked more than 20 packs of cigarettes ever, or more than 1 cigarette / day for one year (as of 1 month ago) 17 Former smoker As for Q 13 above, but stopped smoking greater than 1 month prior to interview 18 Non smoker Smoked less than 20 packs of cigarettes ever, or less than 1 cigarette / day for one year (over entire lifetime) 19 Childhood asthma Positive response to: have you ever had asthma? and, was it diagnosed by a physician? and, reports age of onset less than 16 20 Childhood hayfever Positive response to: have you ever had hayfever? and, was it confirmed by a physician? and, reports age of onset less than 16 21 Childhood eczema Positive response to: have you ever had eczema (or scaly, itchy rash in the flexures of the body)? and, was it confirmed by a physician? and, reports age of onset less than 16 22 History of heart disease Positive response to: Have you had treatment for heart trouble in the past 10 years? Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 3, Page 4 of 5 Karasek* Job Demand Control Questionnaire Instrument This is a 12 item questionnaire (top page 17, main questionnaire) that allows for determinants of psychosocial aspects of work. • Questions A-F enquire about task-level control • G-I enquire about psychological demand • J enquires about physical demand • K-L enquires about co-worker social support • M enquires about level of noise perceived on the job. Combining scores (based on a predefined algorithm) from these questions allows for grouping of individual jobs into specific categories Active Jobs are those with high task control and high psychological demand Low Strain Jobs are those with high task control and low psychological demand High Strain Jobs are those with low task control and high psychological demand Passive Jobs are those with low task control and low psychological demand Job strain: psychological demand score / task control score Workplace environment score: average response to each of 4 workplace scales job satisfaction employee/employer relations employee participation in decision making Joint H&S committee relations * Karasek R, Brisson C, Kawakami N, Houtman I, Bongers P, Amick B. (1998). The Job Content Questionnaire (JCQ): asn instrument for internationally comparative assessments of psychosocial job characteristics. J Occup Health Psychology. 3:322-55. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 3, Page 5 of 5 Descriptions of store environment factors: Factor type description outdoor temperature continuous degrees C (range: -8 to 25) indoor temperature continuous degrees C (range: 13 to 26.5) indoor relative humidity continuous % (range: 36 to 74%) water content of indoor air continuous lb water /lb air (range: 0.0046 to 0.0105) Ambient conditions (measured) median family income (in same postal code) - Statistics Canada data continuous based on 1996 census data range: $27,450 to 63,113 days since floors were last washed continuous range: 0 to 13 Store cleanliness factors (as reported by store mgt) glass breaker steam cleaned in past month 2 categories yes / no or not known extent of crowding (visual inspection) 4 categories very crowded / crowded / somewhat crowded / wide open location of breaker relative to empties counter 3 categories adjacent separated by a wall or partial wall separated by distance warehouse size (subjective assess.) 3 categories relatively small/ medium / large store located below grade 2 categories yes / no store located in enclosed mall 2 categories yes / no Store layout factors (field staff observation) outdoor empties kiosk 2 categories yes / no number of glass bins filled on test day (observation) continuous range: 0.25 to 3.75 number of can bins filled on test day continuous range: 0.33 to 5 number of bin changes on test day continuous range: 0 to 2 beer bottle returns in prior month continuous range: 1849 to 31,304 dozen Empties recycling volume factors wine and spirits bottle returns in prior month (data from LDB mgt) continuous range: 3640 to 68,961 number of times bin raked on test day continuous range: 0 to 7 times number of times jams were cleared continuous range: 0 to 3 times spray cleaner used on breaker 2 categories yes / no glass bins covered 2 categories yes / no full bins in store, previous night 2 categories yes / no Activities associated with glass breaking (field staff observation) visually contaminated bottles in glass breaking machine or broken manually 2 categories yes / no Machine factors (field staff observation) type of glass breaking machine 4 categories glass aggregate rotary, single feed rotary, conveyor feed rotary conveyor, hydraulic use of local exhaust system 3 categories never or seldom used used when operating glass breaker always on Employee tasks % of employee time spent, test day: (self-report) stocking shelves continuous range 0 to 100% working on loads / orders continuous range 0 to 100% working at the empties counter or operating the glass breaker continuous range 0 to 100% working at the cash station continuous range 0 to 100% working in an office, elsewhere in the front of the store continuous range 0 to 100% Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 2, Page 1 of 6 UBC School of Occupational and Environmental Hygiene Bioaerosols, Airborne Particulate Matter and Symptoms in BC Liquor Distribution Branch Stores Susan Kennedy, Ray Copes, Michael Brauer, Sonia Na, Barbara Karlen, Victor Leung August 7, 2001 Appendix 2 Detailed exposure sampling protocols Pre-sampling procedures Filter sample preparation Sampling for both inhalable particulate matter and endotoxin was accomplished using portable seven-hole inlet samplers (JS Holdings, Hertfordshire, UK) containing 2µm pore size, 25mm diameter glass fibre filters (Gelman Sciences, Montréal, PQ Canada). In preparation for sampling, it was necessary to establish a pyrogen-free sampling train, to ensure that there were no cross-reactants present which could affect the analysis. Sampler components were first pre-cleaned with soap and water in a sonicator for 30 min. All parts were rinsed with tap water, then cleaned with RO-pure water in a Bransonic® ultrasonic cleaner for 3x30 min, and finally rinsed again with ultra-pure water (Nanopure™), before being dried between sheets of lint-free paper (Kimwipes®). Metal support screens were subjected to the same wash/rinse cycle and then conditioned in an 180oC oven for a minimum of 4 hours. All glass fibre filters were heated at 180oC for a minimum of 4 hrs, followed by equilibration at a stable temperature and relative humidity (21 ± 1oC and 45 ± 5% relative humidity) for at least 48 hours. The filters were pre-weighed in triplicate using a Sartorius Micro® microbalance with 0.001 mg resolution (Sartorius, Göttingen, Germany) and were placed inside the separate pre-cleaned seven-hole samplers. The samplers were then kept sealed until use. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 2, Page 2 of 6 Filter blanks and calculations At least one filter was used as a field blank for each sampling visit (at least 2 and at most 7 filters), treated identically to the sample filters except without air drawn through them. Monthly average field filter blank weights were used in lieu of an overall average field blank weight to account for the possibility of seasonal trends affecting filter weight gain or loss. These were subtracted from each month's sample filter weights. A set of 6 filters were also kept as lab blanks to evaluate and control for any systematic bias due to weighing technique and balance-room conditions. The mean deviation from 0 was calculated for the lab blanks, with standard deviations. A mass detection limit was thus calculated as three times the standard deviation of the lab blanks. This mass was first halved (DL/2) before being divided by the volume of each filter sample to arrive at a limit of detection (LOD) for each personal and area sample. All samples falling below the LOD were reported as 18771 CFU.m-3). Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 1 of 29 UBC School of Occupational and Environmental Hygiene Bioaerosols, Airborne Particulate Matter and Symptoms in BC Liquor Distribution Branch Stores Susan Kennedy, Ray Copes, Michael Brauer, Sonia Na, Barbara Karlen, Victor Leung August 7, 2001 Appendix 1 Forms used in this study 1. Informed Consent Form 2. UBC Occupational and Environmental Diseases Unit - Questionnaire 3. Acute Symptoms Questionnaire 4. Store Worksheet Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 2 of 29 Informed Consent Form Investigation of Bioaerosols, Airborne Particulate Matter, and Symptoms at BC Liquor Distribution Stores Principal Investigator: Dr. Susan Kennedy, Professor School of Occupational & Environmental Hygiene phone: 604 822-9577 Co-Investigators: Dr. Michael Brauer, Assoc.Professor (822-9585) Dr. Ray Copes, Clinical Associate (822-4925) School of Occupational & Environmental Hygiene Purpose: I understand the purpose of this project is to study the quality of the work environment in BC retail liquor stores, especially in relation to bottle recycling. The UBC researchers will measure concentrations of dust, moulds, and bacterial products in the air during working days, and record the presence of current or past symptoms among employees in the stores. This store was selected for the study at random, and all employees in this store are being invited to participate. Study procedures: The study involves two parts: measuring exposures and recording symptoms. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 3 of 29 Exposure measurements: I understand that I will be asked to wear a small air sampling device clipped to my collar, for the full work shift. It will be attached to an air pump worn on a belt. The pump weighs about 2 kg (or about 5 lb). The device is collecting a sample of the air breathed on a special filter, which will be analysed later in the UBC laboratory. It takes about 2 minutes in the beginning and end of the work shift to set up and remove the sampler. Questionnaire: I understand that a trained interviewer will ask a series of standard questions about symptoms I may have now or in the past and about my work history. Some additional information will also be collected (eg. age, smoking information, a brief family health history) to help interpret the results. The questionnaire will take about 30 minutes. The testing will be done on two different occasions, each about 1 month apart. Confidentiality: I understand that participation in the study is completely voluntary and all results are confidential. No-one other than the UBC researchers will have access to personal information. Reports will include group information only, it will not be possible to identify individuals, or individual stores, from any report. All computer files and documents will be coded with subject numbers, not names, and kept in a secure office. The information will be analysed for the purpose of this study and will be stored securely and confidentially for comparison purposes for future studies. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 4 of 29 Contact: If I have any questions or want more information about the study, I may contact Dr. Susan Kennedy, Sonia Na, or Barbara Karlen, at 604 822-0837. If I have any concerns about my treatment or rights as a research subject I may contact the Director of Research Services at the University of British Columbia, Dr. Richard Spratley at 822-8598. Consent: I understand that my participation in this study is entirely voluntary and that I may refuse to participate in any or all parts of this study, or withdraw from the study at any time without jeopardy to my employment. I have received a copy of this consent form for my own records. I consent to participate in this study. ____________________________ ____________________________ Name (print) Signature ____________ Date ____________________________ _____________ Signature of Witness Date Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 5 of 29 UNIVERSITY OF BRITISH COLUMBIA OCCUPATIONAL AND ENVIRONMENTAL DISEASES UNIT- QUESTIONNAIRE PERSONAL CHARACTERISTICS *IGNORE all questions enclosed by #######~~~~ The following information will help us to keep in touch with you and will be important to us as we measure your health status. It is confidential and will not be released to another party without your permission. row [01] STUDY [ __ __ ] SITE [ __ __ __ ] VISIT [ __ ] SUBJECT [ __ __ __ __ ] 3-12 Today's date [ __ __ /__ __ /__ __ __ __ ] Time:[ __ __ __ __ ] dd mm yyyy 13-24 Full Name: Last: [________________________________] First: [________________________________] Alternative surname/ Maiden name: [________________________________] 25-40 41-54 55-70 #######~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Social Insurance Number: [__ __ __-__ __ __-__ __ __] ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~####### 71-79 row [02] Address: Apt: [ __ __ __ __ ] 3-6 Street: [_____________________________________] 7-35 City/town: [_____________________________________] 36-55 Province: [ __ __ ] Postal Code [ __ __ __-__ __ __ ] 56-63 Telephone: [(__ __ __ )__ __ __-__ __ __ __ ] 64-73 #######~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Name of family doctor: ________________________________________ Address of family doctor:________________________________________ ________________________________________ Doctor’s consent? 1. Yes________ 0. No_________ [ ] 74 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~####### Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 6 of 29 THE FOLLOWING TO BE COMPLETED BY INTERVIEWER row [03] Date of birth: [ __ __ /__ __ /__ __ __ __ ] dd mm yyyy 3-10 Sex: 1. Male_______ 2. Female_______ 11 [ ] Race: 1. White ______ 4. South Asian ______ 2. East Asian ______ 5. Black ______ 3. First Nations 6. Mixed (specify) ___________________ 12 [ ] Height: ______ feet ______ inches ([ __ __ __ ]cm.) 13 –15 Weight: ______ lbs ([ __ __ __ ]kg.) 16 –18 #######~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ COLD - A. Do you currently have a cold? 1. Yes _____ 0. No ______ 19 [ ] B. Have you had a cold in the last 6 weeks? 1. Yes _____ 0. No ______ 20 [ ] TEST RESULTS (For result letters only) row [04] Test Date FEV1 FVC MMF METH XRAY (litres) (litres) (L/sec) This Study: [ __ __/__ __/__ __ __ __ __.__ __ __.__ __ __.__ __ __ __ ] day month year 3-21 Previous Studies: 1.[__ __/__ __/__ __ __ __ __.__ __ __.__ __ __.__ __ __ __ ] 22-40 2.[__ __/__ __/__ __ __ __ __.__ __ __.__ __ __.__ __ __ __ ] 41-59 3.[__ __/__ __/__ __ __ __ __.__ __ __.__ __ __.__ __ __ __ ] 60-78 row [05] 4.[__ __/__ __/__ __ __ __ __.__ __ __.__ __ __.__ __ __ __ ] 3-21 5.[__ __/__ __/__ __ __ __ __.__ __ __.__ __ __.__ __ __ __ ] 22-40 6.[__ __/__ __/__ __ __ __ __.__ __ __.__ __ __.__ __ __ __ ] 41-59 CODING: PC20 0. >64 XRAY:0. Normal 1. 32-64 1. Pleural abnormality only 2. 16-32 2. Parenchymal abn. only 3. 8-16 3. Both pleural & paren. abn 4. 2-8 8. not done 5. <2 8. not done ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~####### row [06] Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 7 of 29 STUDY [ __ __ ] SITE [ __ __ __ ] VISIT [ __ ] SUBJECT [ __ __ __ __ ] 3-11 Name: Last: ___________________, First: ______________________ Interviewer (initials): [ __ __ ] 12-13 PART TWO. HEALTH HISTORY These are questions mainly about your health. Please answer yes or no. If in doubt about the answer, please answer no. COUGH A . Do you usually have a cough? (count cough with first smoke or first going out of doors. Exclude clearing throat.) 1.Yes_____ 0. No_____ [ ] 14 IF NO to A, ask: B. Do you usually cough at all on getting up or first thing in the morning? 1.Yes_____ 0. No_____ [ ] 15 C. Do you usually cough at all during the rest of the day or night? 1.Yes_____ 0. No_____ [ ] 16 IF YES TO ANY OF ABOVE, ask: D. Do you usually cough like this most days for 3 consecutive months or more during the year? 1.Yes_____ 0. No_____ [ ] 17 E. For how many years have you had this cough? __________________ (number of years) [ __ __ ] 18-19 F. Does the cough improve: on days off? on long holidays? 1.Yes_____ 0. No_____ 1.Yes_____ 0. No_____ [ ] 20 [ ] 21 G. Is there any thing or situation which makes your cough worse? 1.Yes_____ 0. No_____ ____________________ (specify) [ ] 22 [ __ __ ] 23-24 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 8 of 29 PHLEGM A . Do you usually bring up phlegm from your chest? (Count phlegm with first smoke or first going out of doors. Count swallowed phlegm. Exclude phlegm from the nose.) 1.Yes_____ 0. No_____ [ ] 25 IF NO to A, ask: B. Do you usually bring up phlegm at all on getting up or first thing in the morning? 1.Yes_____ 0. No_____ [ ] 26 C. Do you usually bring up phlegm at all during the rest of the day or night? 1.Yes_____ 0. No_____ [ ] 27 IF YES TO ANY OF ABOVE, ask: D. Do you usually bring up phlegm like this most days for 3 consecutive months or more during the year? 1.Yes_____ 0. No_____ [ ] 28 E. For how many years have you had trouble with phlegm? __________________ (number of years) [ __ __ ] 29-30 F. Does the phlegm improve: on days off? on long holidays? 1.Yes_____ 0. No_____ 1.Yes_____ 0. No_____ [ ] 31 [ ] 32 G. Is there any thing or situation which makes the phlegm worse? 1. Yes_____ 0. No_____ ___________________ (specify) [ ] 33 [ __ __ ] 34-35 CHEST COLDS AND ILLNESSES row[07] A. If you get a cold does it usually go down to your chest? (ie. more than half the time) 1.Yes_____ 0. No_____ [ ] 3 B. During the past 3 years, have you had any chest illness that has kept you off work, indoors at home, or in bed? 1.Yes_____ 0. No_____ [ ] 4 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 9 of 29 WHEEZING Does your chest ever sound wheezy or whistling: 1.Yes_____ 0. No_____ [ ] 5 A. When you have a cold? 1.Yes_____ 0. No_____ [ ] 6 B. Occasionally apart from colds? 1.Yes_____ 0. No_____ [ ] 7 C. Most days and nights? 1.Yes_____ 0. No_____ [ ] 8 If yes to B or C, ask: D. Is the wheeze associated with chest tightness or difficulty breathing? 1.Yes_____ 0. No_____ [ ] 9 E. For how many years has this been present? _________________ (number of years) [ __ __ ] 10-11 F. When does the wheeze occur MOST frequently? 1. At work _____ 2. On return home _____ 3. During sleep _____ 4. No difference _____ [ ] 12 G. Does the wheeze improve: on days off? on long holidays? 1.Yes____ 0. No____ 1.Yes____ 0. No____ [ ] 13 [ ] 14 H. Is there any thing or situation which makes you wheeze? (identify all that apply): 1.Yes____ 0. No____ [ ] 15 Exercise Cold air Tobacco smoke Strong odour Fumes or dust Other, specify: 1.Yes___ 0. No___ 1.Yes___ 0. No___ 1.Yes___ 0. No___ 1.Yes___ 0. No___ 1.Yes___ 0. No___ __________________ (specify) [ ] 16 [ ] 17 [ ] 18 [ ] 19 [ ] 20 [ __ __ ] 21-22 I. Is the wheezing worse at any particular time of the year? If yes, when: 1. Yes___ 0. No___ ________________ (season) [ ] 23 [ __ __ ] 24-25 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 10 of 29 CHEST TIGHTNESS A. Do you ever have episodes or attacks of chest tightness? 1.Yes____ 0. No____ [ ] 26 B. If yes: is the chest tightness associated with difficulty in breathing? 1.Yes____ 0. No____ [ ] 27 If yes to B, ask: C. For how many years has this been present? ________________ [ __ __ ] 28-29 D. Do you have chest tightness and difficulty breathing on most days? 1.Yes____ 0. No____ [ ] 30 E. During the past year, how many attacks did you have? 1. None ____ 2. A few (1-3) ____ 3. Several (4-12) ____ 4. Most days ____ [ ] 31 F. Does it improve: on days off? on long holidays? 1.Yes____ 0. No____ 1.Yes____ 0. No____ [ ] 32 [ ] 33 G. Is there any thing or situation which makes your chest tightness worse? (identify all that apply): 1.Yes____ 0. No____ [ ] 34 Exercise Cold air Tobacco smoke Strong odour Fumes or dust Other, specify: 1.Yes___ 0. No___ 1.Yes___ 0. No___ 1.Yes___ 0. No___ 1.Yes___ 0. No___ 1.Yes___ 0. No___ _________________ [ ] 35 [ ] 36 [ ] 37 [ ] 38 [ ] 39 [ __ __ ] 40-41 H.Is your chest tightness worse at any particular time of the year? If yes, when: 1.Yes____ 0. No____ __________________ (season) [ ] 42 [ __ __ ] 43-44 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 11 of 29 SHORTNESS OF BREATH A. Are you troubled by shortness of breath when hurrying on the level or walking up a slight hill? 1.Yes____ 0. No____ [ ] 45 If yes to A, ask: B. Do you have to walk slower than people of your own age, on the level, because of breathlessness? 1.Yes____ 0. No____ [ ] 46 C. Do you have to stop for breath when walking at your own pace on the level? 1.Yes____ 0. No____ [ ] 47 D. Do you ever have to stop for breath after walking about 100 yards (or a few minutes) on the level? 1.Yes____ 0. No____ [ ] 48 E. For how many years have you had shortness of breath? _________________ (number of years) [ __ __ ] 49-50 GENERAL CHEST QUESTIONS 1. At any time in the past 12 months: A. Have you had wheezing or whistling in your chest, when you did not have a cold? 1.Yes____ 0. No____ [ ] 51 B. Have you woken up with a feeling of tightness in your chest? 1.Yes____ 0. No____ [ ] 52 C. Have you been woken by an attack of coughing? 1.Yes____ 0. No____ [ ] 53 D. Have you been woken by an attack of shortness of breath? 1.Yes____ 0. No____ [ ] 54 E. Have you had an attack of shortness of breath that came on during the day when you were not doing anything strenuous? 1.Yes____ 0. No____ [ ] 55 F. Have you had an attack of shortness of breath that came on after you stopped exercising? 1.Yes____ 0. No____ [ ] 56 2. Which of the following statements best describes your breathing? ____1 I rarely have trouble with my breathing ____2 I have regular trouble with my breathing but it always gets completely better ____3 My breathing is never quite right [ ] 57 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 12 of 29 NASAL SYMPTOMS 1. Do you ever have sneezing, or an itchy, runny nose when you do not have a cold? 1.Yes____ 0. No____ [ ] 58 If yes to 1, ask: A. For how many years has this been present? _________________ number of years [ __ __ ] 59–60 B. Does this improve: on days off? on long holidays? 1.Yes____ 0. No____ 1.Yes____ 0. No____ [ ] 61 [ ] 62 2. Do you usually have a stuffy or blocked nose? 1.Yes____ 0. No____ [ ] 63 If yes to 2, ask: A. For how many years has this been present? _________________ number of years [ __ __ ] 64–65 B. Does this improve: on days off? on long holidays? 1.Yes____ 0. No____ 1.Yes____ 0. No____ [ ] 66 [ ] 67 If yes to 1 or 2 or BOTH, ask: C. Is there any thing or situation that makes the nasal symptoms worse? 1.Yes____ 0. No____ [ ] 68 D. If yes, specify: ____________________________________ __________________ (specify) Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 13 of 29 EYE SYMPTOMS 1. Do you usually have burning, itching, watering eyes? 1.Yes____ 0. No____ [ ] 69 If yes to 1, ask: A. For how many years has this been present? _________________ number of years [ __ __ ] 70-71 B. Does this occur on most days? 1.Yes____ 0. No____ [ ] 72 C. Does this improve: on days off? on long holidays? 1.Yes____ 0. No____ 1.Yes____ 0. No____ [ ] 73 [ ] 74 D. Is there any thing or situation which makes your eye symptoms worse? E. If yes, specify: ________________________ 1.Yes____ 0. No____ __________________ (specify) [ ] 75 [ __ __ ] 76-77 OTHER CONDITIONS row [08] 1. Have you ever had asthma? 1.Yes____ 0. No____ [ ] 3 IF YES TO '1', ask: A. Do you still have it? 1.Yes____ 0. No____ [ ] 4 B. Was it confirmed by a doctor? 1.Yes____ 0. No____ [ ] 5 C. At what age did it start? ________________ (enter age) [ __ __ ] 6-7 D. If you no longer have it, at what age did it stop? ___________________ (enter age) [ __ __ ] 8–9 2. Have you ever had hayfever? 1.Yes____ 0. No____ [ ] 10 IF YES TO '2', ask: A. Do you still have it? 1.Yes____ 0. No____ [ ] 11 B. Was it confirmed by a doctor? 1.Yes____ 0. No____ [ ] 12 C. At what age did it start? ________________ (enter age) [ __ __ ] 13-14 D. If you no longer have it, at what age did it stop? ___________________ (enter age) [ __ __ ] 15–16 1.Yes____ 0. No____ [ ] 17 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 14 of 29 3. Have you ever had eczema? (scaly, itchy rash in the flexures of the body) IF YES TO '3', ask: A. Do you still have it? 1.Yes____ 0. No____ [ ] 18 B. Was it confirmed by a doctor? 1.Yes____ 0. No____ [ ] 19 C. At what age did it start? ________________ (enter age) [ __ __ ] 20-21 D. If you no longer have it, at what age did it stop? ___________________ (enter age) [ __ __ ] 22-23 #######~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ALLERGY SKIN TEST RESULTS Agent Measurement (mm); check if not done (code 88) 1. D. farinae __________ ( ______ ) [ __ __ ] 24-25 2. Mixed grass pollen __________ ( ______ ) [ __ __ ] 26-27 3. Cat fur __________ ( ______ ) [ __ __ ] 28-29 4. Histamine __________ ( ______ ) [ __ __ ] 30-31 5. Control __________ ( ______ ) [ __ __ ] 32-33 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~####### PAST CHEST ILLNESSES row [09] 1. Did you have any lung trouble before the age of 16? 1.Yes____ 0. No____ [ ] 3 2. Have you ever had pneumonia? 1.Yes____ 0. No____ [ ] 4 IF YES TO '2', ask: A. How many times have you had pneumonia? ________________ [ __ __ ] 5-6 B. Age at first episode: ________________ (enter age) [ __ __ ] 7-8 C. Age at last episode: ___________________ (enter age) [ __ __ ] 9-10 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 15 of 29 3. Have you ever had any other chest illnesses? If yes, specify: ________________________ 1.Yes____ 0. No____ _________________ (specify) [ ] 11 4. Have you ever had any chest injuries? If yes, specify: ________________________ 1.Yes____ 0. No____ [ ] 12 5. Have you ever had any chest operations? If yes, specify: ____________________________________ 1.Yes____ 0. No____ [ ] 13 6. Are you currently taking any medications for your breathing? If yes, specify: ____________________________________ 1.Yes____ 0. No____ [ ] 14 (CODE 1 if chest illness, injury, or operation interferes with current lung function) [ ] 15 7. Have you ever had any of the following? (1st box) If yes, was it confirmed by a doctor? (2nd box) Age started A. Attacks of bronchitis 1.Yes ____ 0. No ____ 1.Yes ___ 0. No ____ [ __ __ ] 16-17 [ ] [ ] 18 19 B. Chronic bronchitis 1.Yes ____ 0. No ____ 1.Yes ___ 0. No ____ [ __ __ ] 20-21 [ ] [ ] 22 23 C. Emphysema 1.Yes ____ 0. No ____ 1.Yes ___ 0. No ____ [ __ __ ] 24-25 [ ] [ ] 26 27 D. Pulmonary tuberculosis 1.Yes ____ 0. No ____ 1.Yes ___ 0. No ____ [ __ __ ] 28-29 [ ] [ ] 30 31 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 16 of 29 CARDIOVASCULAR AND OTHER HEALTH HISTORY 1. Has a doctor ever told you that you had heart trouble? 1.Yes____ 0. No____ [ ] 32 If yes: Have you had treatment for heart trouble in the past 10 years? 1.Yes____ 0. No____ [ ] 33 2. Has a doctor ever told you that you had high blood pressure? 1.Yes____ 0. No____ [ ] 34 If yes: Have you had treatment for high blood pressure in the past 10 years? 1.Yes____ 0. No____ [ ] 35 3. Do you have any other health problems? If yes, specify: ____________________________________ 1.Yes____ 0. No____ [ ] 36 4. Are you taking any medications for other illnesses at present? If yes, specify: ____________________________________ CODE 1 if other illness(es) interfere with current spirometry 1.Yes____ 0. No____ [ ] 37 [ ] 38 5. Currently, would you say your overall health is: Excellent ___ Good ___ Fair ___ Poor ___ Bad ___ [ ] 39 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 17 of 29 The following questions are about some habits that are important to us in evaluating your health. Please answer to the best of your memory. TOBACCO SMOKING SMOKING BY PEOPLE LIVING AROUND YOU: row [10] When you lived at home: 1. Did your father smoke? 1.Yes____ 0. No____ [ ] 3 2. Did your mother smoke? 1.Yes____ 0. No____ [ ] 4 In your current household: 3. Do any members of your current household smoke (other than you)? 1.Yes____ 0. No____ [ ] 5 YOUR SMOKING: 1. Have you ever smoked cigarettes? (No means less than 20 packs of cigarettes ever, or less than one cigarette a day for one year.) 1.Yes____ 0. No____ [ ] 6 If yes , ask: A. Do you now smoke cigarettes (as of 1 month ago)? 1.Yes____ 0. No____ [ ] 7 B. How old were you when you first started regular cigarette smoking? ____________years [ __ __ ] 8-9 C. If you have stopped smoking cigarettes completely, how old were you when you stopped? ____________years [ __ __ ] 10-11 D. How many cigarettes do you smoke per day now? ________________ cigarettes per day [ __ __ ] 12-13 E. On average, for the entire time that you smoked, how many cigarettes did you smoke per day? __________________ cigarettes per day [ __ __ ] 14-15 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 18 of 29 PIPE SMOKING 1. Have you ever smoked a pipe? (Yes means more than 12 oz of pipe tobacco ever.) 1.Yes_____ 0. No_____ [ ] 16 If yes , ask: A. Do you now smoke a pipe (as of 1 month ago)? 1.Yes_____ 0. No_____ [ ] 17 B. How old were you when you first started smoking a pipe regularly? ______________years [ __ __ ] 18-19 C. If you have stopped smoking a pipe completely, how old were you when you stopped? ______________years [ __ __ ] 20-21 D. How much pipe tobacco do you smoke per week now? __________________ ounces per week [ __ __ ] 22-23 E. On average, for the entire time that you smoked a pipe, how much pipe tobacco did you smoke per week? __________________ ounces per week [ __ __ ] 24-25 CIGAR SMOKING 1. Have you ever smoked cigars regularly? (Yes means more than 1 cigar a week for a year.) 1.Yes_____ 0. No_____ [ ] 26 If yes , ask: A. Do you now smoke cigars (as of 1 month ago)? 1.Yes_____ 0. No_____ [ ] 27 B. How old were you when you first started smoking cigars regularly? ______________years [ __ __ ] 28-29 C. If you have stopped smoking cigars completely, how old were you when you stopped? ______________years [ __ __ ] 30-31 D. How many cigars do you smoke per week now? __________________ cigars per week [ __ __ ] 32-33 E. On average, for the entire time that you smoked cigars, how many cigars did you smoke per week? __________________ cigars per week [ __ __ ] 34-35 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 19 of 29 FAMILY HISTORY As some illnesses are associated with childhood and family history we would like to ask you about your family members, and about your childhood. 1. Was your natural father ever told by a doctor that he had: 1.Yes 0. No 3.Don’t know A. Chronic bronchitis [ ] 36 B. Emphysema [ ] 37 C. Lung cancer [ ] 38 D. Asthma [ ] 39 E. Other chest condition [ ] 40 F. Hayfever [ ] 41 G. Other allergic condition [ ] 42 2. Was your natural mother ever told by a doctor that she had: A. Chronic bronchitis [ ] 43 B. Emphysema [ ] 44 C. Lung cancer [ ] 45 D. Asthma [ ] 46 E. Other chest condition [ ] 47 F. Hayfever [ ] 48 G. Other allergic condition [ ] 49 3. Your country (province) of birth: ____________________ [ __ __ ] 50-51 4. In what country did you spend the majority of the first 10 years of your life? ____________________ [ __ __ ] 52-53 5. Were these first 10 years spent in the: (check one only) Countryside 1. ______ Town -smaller than 10,000 people 2. ______ -10,000 to 100,000 people 3. ______ -larger than 100,000 people 4. ______ [ ] 54 6. What was your father’s occupation: ____________________ [ ] 55 7. What was your mother’s occupation: ____________________ [ ] 56 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 20 of 29 CURRENT JOB The following questions are about your current job: row [11] 1. Employer: BC Liquor Distribution Branch; LDB Employee Number [ __ __ __ __ ] 3-6 2. Industry type (SIC): [ __ __ __ ] 7-9 3. Job title: 1.______ Clerk 2.______Assistant manager: 3.______Store manager: 4.______Other (specify): __________________________ [ ] 10 4. What is your present work status: 1. _______ regular f/ t, working 2. _______ regular f/ t, but not working due to illness or disability 3. _______ regular f/ t, but not working due to vacation or other leave 4. _______auxiliary, working 5. _______auxiliary, but not working due to illness or disability 6. _______auxiliary, but not working due to vacation or other leave 7. _______other, specify: ________________________________ [ ] 11 5. If not working due to sickness, disability, or leave What date did you last work? [ __ __ /__ __/__ __ __ __ ] dd mm yyyy 12-19 6. Total number of years in this job? _______________ (code months: ____________ ) [ __ __ __ ] 20-22 7. Total number of years with this employer? ______________ (code months: ________ ) [ __ __ __ ] 23-25 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 21 of 29 8. The following are some statements describing aspects of SOME jobs. Please tell me if you agree or disagree with each of the following, with respect to your CURRENT job. Strongly disagree Disagree Agree Strongly agree A. Your job requires learning new things [ ] 26 B. Your job involves a lot of repetitive work [ ] 27 C. Your job requires a high level of skill [ ] 28 D. Your job has a variety of tasks [ ] 29 E. You have a lot to say about what happens on the job [ ] 30 F. On this job, you have a lot of freedom to decide how to do the work [ ] 31 G. Your job does not involve an excessive amount of work [ ] 32 H. You have enough time to get the job done [ ] 33 I. Your job is free from conflicting demands [ ] 34 J. Your job requires lots of physical effort [ ] 35 K. You can leave this job to talk with co-workers [ ] 36 L. You can interact with co-workers while you work [ ] 37 M. Your job is noisy [ ] 38 WORKPLACE ENVIRONMENT 1. Please rate the following on a one to ten scale: Rating A. Job satisfaction for most workers in your store (NOTE: for auxiliaries, use \"recall area\" instead of \"store\") POOR....2....3....4....5....6....7....8....9....EXCELLENT ______ [ __ __ ] 39-40 B. Employee/ employer relations in your store (recall area)? POOR....2....3....4....5....6....7....8....9....EXCELLENT ______ [ __ __ ] 41-42 C. Extent of worker participation in decision making at your store (recall area) NO participation....2....3....4....5....6....7....8....9....EXTENSIVE participation ______ [ __ __ ] 43-44 D. Degree of co-operation that exists between worker and employer members of the Joint H&S committee: NO co-operation....2....3....4....5....6....7....8....9....HIGH degree of co-operation ______ [ __ __ ] 45-46 Comments_________________________________________________________________________________ Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 22 of 29 PREVIOUS JOBS WITH THIS EMPLOYER 1. List previous jobs with this employer; start with the MOST RECENT and WORK BACKWARDS: row [12] From (year) To (year) Job title Location (store) Comments, details 1 [ ] 3-6 [ ] 7-10 [ __ __ __ ] [ __ __ __ ] 11-16 2 [ ] 17-20 [ ] 21-24 [ __ __ __ ] [ __ __ __ ] 25-30 3 [ ] 31-34 [ ] 35-38 [ __ __ __ ] [ __ __ __ ] 39-44 4 [ ] 45-48 [ ] 49-52 [ __ __ __ ] [ __ __ __ ] 53-58 5 [ ] 59-62 [ ] 63-66 [ __ __ __ ] [ __ __ __ ] 67-72 PREVIOUS JOBS WITH OTHER EMPLOYERS: Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 23 of 29 1. Please list your jobs from the first job you had on leaving school that LASTED LONGER THAN SIX MONTHS (before you started with your current employer). Start with your FIRST JOB since leaving school and WORK FORWARDS: row [13] From (year) To (year) 1 [ ] 3-6 [ ] 7-10 Job title: ______________________________ Type of company or industry: ______________ ______________________________________ Comments: ____________________________ [__ __ __ __] [__ __ __ __] 11-18 2 [ ] 19-22 [ ] 23-26 Job title: ______________________________ Type of company or industry: ______________ ______________________________________ Comments: ____________________________ [__ __ __ __] [__ __ __ __] 27-34 3 [ ] 35-38 [ ] 39-42 Job title: ______________________________ Type of company or industry: ______________ ______________________________________ Comments: ____________________________ [__ __ __ __] [__ __ __ __] 43-50 4 [ ] 51-54 [ ] 55-58 Job title: ______________________________ Type of company or industry: ______________ ______________________________________ Comments: ____________________________ [__ __ __ __] [__ __ __ __] 59-66 row [13] 5 [ ] 3-6 [ ] 7-10 Job title: ______________________________ Type of company or industry: ______________ ______________________________________ Comments: ____________________________ [__ __ __ __] [__ __ __ __] 11-18 6 [ ] 19-22 [ ] 23-26 Job title: ______________________________ Type of company or industry: ______________ ______________________________________ Comments: ____________________________ [__ __ __ __] [__ __ __ __] 27-34 7 [ ] 35-38 [ ] 39-42 Job title: ______________________________ Type of company or industry: ______________ ______________________________________ Comments: ____________________________ [__ __ __ __] [__ __ __ __] 43-50 8 [ ] 51-54 [ ] 55-58 Job title: ______________________________ Type of company or industry: ______________ ______________________________________ Comments: ____________________________ [__ __ __ __] [__ __ __ __] 59-66 CURRENT OR OTHER EXPOSURES row [14] Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 24 of 29 1. Have you ever worked in, or been exposed to any of the following for more than six months at a time: 1 YES Start year How long?(yrs) 1. Asbestos milling/manufacture [ ] [ __ __ __ __ ] [ __ __ ] 3-9 2. Asbestos removal [ ] [ __ __ __ __ ] [ __ __ ] 10-16 3. Asbestos dust in other jobs [ ] [ __ __ __ __ ] [ __ __ ] 17-23 4. Brake or clutch repair [ ] [ __ __ __ __ ] [ __ __ ] 24-30 5. Boilermaking/repair [ ] [ __ __ __ __ ] [ __ __ ] 31-37 6. Building maintenance/repair [ ] [ __ __ __ __ ] [ __ __ ] 38-44 7. Construction [ ] [ __ __ __ __ ] [ __ __ ] 45-51 7a. What trade(s)? _______________ [ __ __ ] 52-53 8. Shipbuilding or repair [ ] [ __ __ __ __ ] [ __ __ ] 54-60 row [15] 9. Sawmill [ ] [ __ __ __ __ ] [ __ __ ] 3-9 9a Cedar dust exposure? [ ] 10 10. Painting [ ] [ __ __ __ __ ] [ __ __ ] 11-17 10a. With 2 component paint? [ ] 18 11. Spray foam applications [ ] [ __ __ __ __ ] [ __ __ ] 19-25 12. Anaesthetic gases [ ] [ __ __ __ __ ] [ __ __ ] 26-32 13. Auto repair or manufacture [ ] [ __ __ __ __ ] [ __ __ ] 33-39 14. Chemical or rubber manufacture [ ] [ __ __ __ __ ] [ __ __ ] 40-46 15. Drycleaning [ ] [ __ __ __ __ ] [ __ __ ] 47-53 16. Electronic equipment manufacture [ ] [ __ __ __ __ ] [ __ __ ] 54-60 17. Farm, nursery, landscaping work [ ] [ __ __ __ __ ] [ __ __ ] 61-66 row [16] 18. Firefighting [ ] [ __ __ __ __ ] [ __ __ ] 3-9 19. Fishing/other maritime work [ ] [ __ __ __ __ ] [ __ __ ] 10-16 20. Flour or grain handling [ ] [ __ __ __ __ ] [ __ __ ] 17-23 21. Foundry or metal fabrication [ ] [ __ __ __ __ ] [ __ __ ] 24-30 22. Furniture making [ ] [ __ __ __ __ ] [ __ __ ] 31-37 23. Laboratory work [ ] [ __ __ __ __ ] [ __ __ ] 38-44 23a What type? [ __ __ ]type 45-46 24. Longshoring [ ] [ __ __ __ __ ] [ __ __ ] 47-53 25. Metal processing [ ] [ __ __ __ __ ] [ __ __ ] 54-60 row [17] 26. Mining, quarrying [ ] [ __ __ __ __ ] [ __ __ ] 3-9 26a Type of minerals (and specify if worked underground [UG]) [ ] [ ] [ ] 1=UG [ __ __ ] [ __ __ ] [ __ __ ] type [ __ __ ] [ __ __ ] [ __ __ ] 10-24 27 Non-asbestos insulation (eg.fibreglass, mineral wool) [ ] [ __ __ __ __ ] [ __ __ ] 25-31 28 Nuclear power plant [ ] [ __ __ __ __ ] [ __ __ ] 32-38 29 Petroleum processing [ ] [ __ __ __ __ ] [ __ __ ] 39-45 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 25 of 29 30 Plastics manufacture [ ] [ __ __ __ __ ] [__ __] 46-52 31 Plywood manufacture [ ] [ __ __ __ __ ] [__ __] 53-59 32 Pottery [ ] [ __ __ __ __ ] [__ __] 60-66 33 Pulp and paper [ ] [ __ __ __ __ ] [__ __] 67-73 34 Railway maintenance work [ ] [ __ __ __ __ ] [__ __] 74-80 row [18] 35 Roofing [ ] [ __ __ __ __ ] [__ __] 3-9 36 Sandblasting [ ] [ __ __ __ __ ] [__ __] 10-16 37 Smelter [ ] [ __ __ __ __ ] [__ __] 17-23 37a Smelter type: ______________ [__ __] 24-25 38 Steelmill [ ] [ __ __ __ __ ] [__ __] 26-32 39 Textile milling or processing [ ] [ __ __ __ __ ] [__ __] 33-39 39a Cotton dust exposure? [ ] [ __ __ __ __ ] [__ __] 40-46 40 Welding [ ] [ __ __ __ __ ] [__ __] 47-53 40a Type of welding:_____________ [__ __] 54-55 40b In enclosed spaces? [ ] [ __ __ __ __ ] [__ __] 56-62 41 Wood treating [ ] [ __ __ __ __ ] [__ __] 63-69 row [19] 2. In any job, have you ever been exposed to a high concentration of gas or fumes that made you sick or that sent you to first aid or to the doctor? Specify: ______________ __________________________________________________ 1.Yes____ 0. No____ [ ] 3 3. Have you ever had any health problems apart from accidents or injuries, that you feel were caused by your job with your current employer? Specify: ___________________________ ___________________________________________________ 1.Yes_____ 0. No_____ [ ] 4 4. Have you ever had any health problems that you feel were caused by a job with another employer? Specify: _______ ___________________________________________________ 1.Yes____ 0. No____ [ ] 5 5. Have you ever left a job for health reasons only? If YES, What was the job and what was the nature of the problem? __________________________________________________ __________________________________________________ 1.Yes____ 0. No____ [ ] 6 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 26 of 29 ACUTE SYMPTOMS QUESTIONNAIRE: One for each employee sampled row [31] Study Number [ __ __ ] Site [ __ __ __ ] Visit : [ __ ] Subject Number: [ __ __ __ __ ] 3-12 Date: [ __ __ / __ __ / __ __ __ __ ] Sample Number: [ LDB - __ __ __ ] 13-23 dd mm yyyy 1. In the past week, have you experienced any of the following? How often? How much did it bother you? NO (0) YES (1) once (1) more than once, but not every day (2) every day (3) only a little (1) some (2) very much (3) row [32] 1. Dry cough ___ ___ ___ ___ ___ ___ ___ ___ 3-5 2. Cough with phlegm ___ ___ ___ ___ ___ ___ ___ ___ 6-8 3. Wheezing ___ ___ ___ ___ ___ ___ ___ ___ 9-11 4. Chest tightness ___ ___ ___ ___ ___ ___ ___ ___ 12-14 5. Breathlessness ___ ___ ___ ___ ___ ___ ___ ___ 15-17 6. Irritated nose ___ ___ ___ ___ ___ ___ ___ ___ 18-20 7. Runny/stuffy nose ___ ___ ___ ___ ___ ___ ___ ___ 21-23 8. Irritated throat ___ ___ ___ ___ ___ ___ ___ ___ 24-26 9. Sinus trouble ___ ___ ___ ___ ___ ___ ___ ___ 27-29 10. Irritated eyes ___ ___ ___ ___ ___ ___ ___ ___ 30-32 11. Vision disturbances ___ ___ ___ ___ ___ ___ ___ ___ 33-35 12. Taste disturbances ___ ___ ___ ___ ___ ___ ___ ___ 36-38 13. Voice disturbances ___ ___ ___ ___ ___ ___ ___ ___ 39-41 14. Fever ___ ___ ___ ___ ___ ___ ___ ___ 42-44 15. Headache ___ ___ ___ ___ ___ ___ ___ ___ 45-47 16. Dizziness ___ ___ ___ ___ ___ ___ ___ ___ 48-50 17. Tiredness ___ ___ ___ ___ ___ ___ ___ ___ 51-53 18. Joint pains ___ ___ ___ ___ ___ ___ ___ ___ 54-56 19. Skin irritation ___ ___ ___ ___ ___ ___ ___ ___ 57-59 20. Bleeding from nose ___ ___ ___ ___ ___ ___ ___ ___ 60-62 21. Other unusual bleeding (specify) _________________ ___ ___ ___ ___ ___ ___ ___ ___ 63-65 22. Infections (specify type and location) _________________ ___ ___ ___ ___ ___ ___ ___ ___ 66-68 23. Any other symptoms? (specify) ___ ___ ___ ___ ___ ___ ___ ___ 69-71 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 27 of 29 TODAY IN THE STORE—ONE FOR EACH EMPLOYEE SAMPLED Sample Number: LDB - ____________ row [33] 1. TODAY's store site _______________________ [ __ __ __ ] store name location code 3-5 2. START: STOP: [ __ __ __ __ ]h (24h time) [ __ __ __ __ ]h 6-13 2. What store did you work at YESTERDAY? _______________________ [ __ __ __ ] 14-16 3. Hours worked: Today Yesterday Past week Past month [ __ __ ]hrs [ __ __ ]hrs [ __ __ ]hrs [ __ __ __ ]hrs 17-25 4. % time spent doing the following tasks? ________________________________ ________________________________ ________________________________ ________________________________ ________________________________ (note hour breakdown here if preferred) 1. Cashier [ __ __ __ ] 2. Stocking shelves [ __ __ __ ] 3. Empties / breakage [ __ __ __ ] 4 Liquor loads/ orders [ __ __ __ ] 5. Office/ customer service [ __ __ __ ] 6. Other [ __ __ __ ] _____________________________________ 26-43 5. On average over the past month, how often do you wear respiratory protection? 1. Never/ almost never (then 39-41 all='0') 2. Sometimes: a-operating glass breaker b-moving glass bins c-other______________________ 3. Always/ mostly: a-operating glass breaker b-moving glass bins c-other____________________ [ ] 44 (1,2, or 3) [ __ __ __ ] 45-47 (1='YES'; 0='NO') 6. On average over the past month, how often do you wear gloves? 1. Never/ almost never 2. Sometimes: a-operating glass breaker b-moving glass bins c-other______________________ 3. Always/ mostly: a-operating glass breaker b-moving bins c-other____________________ [ ] 48 [ __ __ __ ] 49-51 7. On average over the past month, how often do you wear eye shields/ safety glasses? 1. Never/ almost never 2. Sometimes: a-operating glass breaker b-moving glass bins c-other______________________ 3. Always/mostly: a-operating glass breaker b-moving glass bins c-other____________________ [ ] 52 [ __ __ __ ] 53-55 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 28 of 29 STORE WORKSHEET—ONE PER STORE PER VISIT STORE: ______________________________ LOCATION CODE: __________ row [35] 1. Date: [ __ __ / __ __ / __ __ __ __ ] Visit: ___________ 3-11 2. # Employees in store # Employees sampled ____________ ____________ [ __ __ ] 12-13 [ __ __ ] 14-15 3. # glass bins filled in period ____________ [ __ __ ] 16-17 4. # can bins filled in period ____________ [ __ __ ] 18-19 5. Empties stored overnight? 1. Yes 0. No 5a If YES, how many (on avg): ______________units 20 [ __ __ __ ] 21-23 6.A Total # times glass raked ____________times (see tally sheet) [ __ __ ] 24-25 B Total # times jams cleared ____________times [ __ __ ] 26-27 C Total # glass bin changes ____________times [ __ __ ] 28-29 D Total # times spray used ____________times [ __ __ ] 30-31 8. Problem bottles put through? 1. Yes 0. No Details:__________________________ [ ] 32 9. Dust filter unit 'ON' all day? 1. Yes 0. No If NO, when is it operating? 1. Immediately pre/post glass breaking 2. Period before and after (specify): _______min [ ] 33 [ ] 34 10. Machine type 10a. Is the bin covered? 10b. Is it a conveyor? 10bi Length: 1. Rotary single feed 2. Rotary conveyor 3. Glass aggregate 4. Conveyor w/barrel 5. Rotary conveyor (hydraulic) 1. Yes 0. No 1. Yes 0. No __________feet (code cm) [ __ __ __ ]cm [ ] 35 [ ] 36 [ ] 37 38-40 11. T [ __ __ . __ ] °C dry (avg AM and PM) 41-43 12. RH ___________°C wet RH = [ __ __ ] % (avg AM and PM) 44-45 13. Main duct: ventilation 14.A Diameter: B Discharge location C Static pressure 15.A From-bin hose ventilation B Diameter: C. Static pressure [ __ __ __ __ ] ft/min (average 3 velocity readings) [ __ __ ] inches Rating: [ __ __ __ __ ] cfm 1. Wall 2. Roof [ __ . __ ] inches of water on: ( ) inlet ( ) outlet side [ __ __ __ __ ] ft/ min (avg 3 velocity readings [ __ ] inches Rating: [ __ __ __ __ ] cfm [ __ . __ ] inches of water on ( ) inlet ( ) outlet side 46-49 50-55 [ ] 56 57-58 59-62 63-67 68-69 17. Bulk sample collected? 1. Yes 0. No ID: LDB-B [__ __ ] 70-72 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Appendix 1, Page 29 of 29 Total viable airborne mesophilic fungi: sampling worksheet 17. TFC: row [36] 1. F - __ __ __ 2. F - __ __ __ 3. F - __ __ __ 4. F - __ __ __ 5. F - __ __ __ 6. F - __ __ __ 7. F - __ __ __ 8. F - __ __ __ 9. F - __ __ __ START [ __ __ : __ __ ] [ __ __ : __ __ ] [ __ __ : __ __ ] [ __ __ : __ __ ] [ __ __ : __ __ ] [ __ __ : __ __ ] [ __ __ : __ __ ] [ __ __ : __ __ ] [ __ __ : __ __ ] DURATION (sec) [ __ __ __ ] [ __ __ __ ] [ __ __ __ ] [ __ __ __ ] [ __ __ __ ] [ __ __ __ ] [ __ __ __ ] [ __ __ __ ] [ __ __ __ ] LOCATION [ __ ] [ __ ] [ __ ] [ __ ] [ __ ] [ __ ] [ __ ] [ __ ] [ __ ] COUNT (cfu/ m3) [ __ __ __ __ __ __ ] [ __ __ __ __ __ __ ] [ __ __ __ __ __ __ ] [ __ __ __ __ __ __ ] [ __ __ __ __ __ __ ] [ __ __ __ __ __ __ ] [ __ __ __ __ __ __ ] [ __ __ __ __ __ __ ] [ __ __ __ __ __ __ ] 3-19 20-36 37-53 row [37] 3-19 20-36 37-53 row [38] 3-19 20-36 37-53 LOCATION NOTES: Please be specific about where you placed the sampler: Number, ID Location 1. F - __ __ __ 2. F - __ __ __ 3. F - __ __ __ 4. F - __ __ __ 5. F - __ __ __ 6. F - __ __ __ 7. F - __ __ __ 8. F - __ __ __ 9. F - __ __ __ VENTILATION / LAYOUT / MAINTENANCE NOTES: 1. Date of last maintenance:_______________ Type:_________________________________ 2. Cleaning dates:______________________ Type:_________________________________ 3. Date of last cleaning:_________________ Was it a regularly scheduled one? Y N - What day are floors done? M T W R F S Su - General appearance of area surrounding breaker/ empties counter? (Cleanliness, odours?) _____________________________________________________________________________ Investigation of Bioaerosols, Airborne Particulate Matter, and Symptoms at BC Liquor Distribution Branch Stores Final Report: August 7, 2001 Susan Kennedy, Ray Copes, Michael Brauer, Sonia Na, Victor Leung, Barbara Karlen UBC School of Occupational and Environmental Hygiene 3rd Floor, 2206 East Mall, Vancouver BC, V6T 1Z3 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 2 of 76 Contents Contents .......................................................................................................................................................................2 List of tables and figures ...............................................................................................................................................3 1 Executive Summary ..........................................................................................................................................5 1.1 Study design and methods.............................................................................................................................5 1.2 Personal and area monitoring results .............................................................................................................5 1.3 Symptoms and their relationship to exposures ..............................................................................................6 1.4 Conclusions ..................................................................................................................................................8 2 Introduction .....................................................................................................................................................8 3 Background ....................................................................................................................................................10 4 Methods .........................................................................................................................................................13 4.1 Study design and general protocol ...............................................................................................................13 4.2 Personal and Area Monitoring ...................................................................................................................15 4.3 Symptom Assessment .................................................................................................................................19 4.4 Data management and analysis....................................................................................................................19 5 Results: Sites and participants.........................................................................................................................23 5.1 Participation ...............................................................................................................................................23 5.2 Sites included compared to those not included ............................................................................................23 5.3 Store characteristics: environment, equipment, and procedures ...................................................................25 6 Results: Dust, endotoxin and fungal levels .....................................................................................................29 6.1 Summary results..........................................................................................................................................29 6.2 Airborne contaminant levels, according to visit, study group .......................................................................35 6.3 Seasonal trends ...........................................................................................................................................36 6.4 Regional differences in contaminant levels ..................................................................................................38 6.5 Work activities associated with fungal levels ................................................................................................39 6.6 Store environment and work activities contributing to contaminant levels 43 7 Results: Characteristics of participants............................................................................................................51 7.1 Demographic and health history characteristics of participants....................................................................51 7.2 Psycho-social aspects of work .....................................................................................................................53 7.3 Chronic symptom prevalence rates..............................................................................................................54 7.4 Acute symptoms .........................................................................................................................................55 8 Results: Relationships between contaminant levels and symptoms .................................................................60 8.1 Acute symptoms .........................................................................................................................................60 8.2 Exposure-response relationships (multivariable analyses): ...........................................................................62 8.3 Cross-sectional analysis of chronic symptoms (visit 1 results) ......................................................................65 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 3 of 76 9 Summary and Discussion ................................................................................................................................67 9.1 Exposures...................................................................................................................................................67 9.2 Employee symptoms...................................................................................................................................69 9.3 Relationship between work exposures and symptoms .................................................................................70 9.4 Psychosocial aspects of work: impact on symptoms ....................................................................................72 10 Conclusions ...................................................................................................................................................74 11 References ......................................................................................................................................................75 12 Appendices .....................................................................................................................................................76 List of tables and figures Table 1: Store environment factors 18 Table 2: Participation summary 23 Table 3: Comparison of study sites to all BC liquor stores 24 Table 4: Store characteristics, by study group 25 Table 5: Store environment characteristics and recycling activities, by visit, group 26 Table 6: Volume of empties, by machine type and presence of outdoor kiosk 28 Table 7: Inhalable particulate sample results, averages based on individual filters. 29 Table 8: Viable fungal counts (CFU/m3), by sampling location 30 Table 9: Comparison exposure data from BC worksites 34 Table 10: Dust, Endotoxin, and Viable Fungal levels, by visit and study arm 35 Figure 1: Fungal levels by visit and month 37 Figure 3: Contaminant levels by region 38 Figure 4: Viable fungal counts: samples taken near the glass breaker (when operating) compared to samples elsewhere in the warehouse, by region, visit 39 Figure 5: Viable fungal counts: all samples near the breaker (operating and not), compared to samples taken in the warehouse (away from the breaker) 40 Table 11: Store environment and work activity factors evaluated 41 Table 12: Factors (continuous variables) associated with indoor personal dust exposure (log scale) – correlation coefficients 42 Table 13: Factors (categorical variables) associated with indoor personal dust exposure (log scale) – comparison of geometric mean values 42 Table 14: Coefficients from the ‘best fit’ multiple linear regression model for inhalable particulate (ln transformed) 44 Table 15: Factors (continuous variables) associated with indoor personal endotoxin exposure (log scale) – correlation coefficients 45 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 4 of 76 Table 16: Factors (categorical variables) associated with indoor endotoxin exposure (log scale) – comparison of geometric mean values 45 Table 17: Coefficients from the ‘best fit’ multiple linear regression model for endotoxin (ln transformed) 46 Table 18: Factors (continuous variables) associated with indoor viable fungal levels (log scale) – correlation coefficients 47 Table 19: Factors (categorical variables) associated with indoor endotoxin exposure (log scale) – comparison of geometric mean values 48 Table 20: Coefficients from the ‘best fit’ multiple linear regression model for store average (indoor) fungal counts (ln transformed) 49 Table 21 : Jobs of participants, according to test occasion 51 Table 22 - Demographic and general health characteristics of participants 52 Table 23: Chronic symptoms: LDB employees compared to BC Ferry Corporation employees 54 Table 24: Acute symptom prevalence, by visit, group 56 Table 25: Acute symptom complexes, by visit and group 58 Table 26: Acute symptoms and symptom complexes by smoking status 59 Table 27: Acute symptoms and symptom complexes by job 59 Table 28: Acute symptoms and symptom complexes by region 59 Table 29: Acute symptom complexes: relationship to dust /endotoxin exposure levels 60 Table 30: Acute symptoms: relationship to peak fungal levels 61 Table 31: Acute symptoms and symptom complexes, according to whether or not visually contaminated bottles were being broken in the store on the test day (by visit) 62 Table 32: Odds ratios from multivariable models for acute symptoms and symptom complexes 64 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 5 of 76 1 Executive Summary 1.1 Study design and methods In June of 2000, the UBC School of Occupational and Environmental Hygiene was asked by the Liquor Distribution Branch (LDB), the British Columbia Government and Service Employees Union (BCGEU), and the Workers’ Compensation Board (WCB) to assess the health impact on LDB employees of the use of glass breaking machines in retail liquor stores. Specifically, the objectives were to measure concentrations of inhalable particulate matter (dust) and two bioaerosol measures (viable fungi and endotoxin), to assess the prevalence of acute and chronic symptoms among LDB employees, and to examine the relationships between exposures and symptoms. We conducted the study at 36 stores, selected at random. These stores were similar to other BC liquor stores and participation rates were high, indicating that the results can be generalized beyond the stores and employees tested. Each store was tested twice, approximately 1 month apart. In half the stores (selected at random), the glass breaking equipment was shut down between visit 1 and visit 2. Dust and endotoxin were measured using personal sampling methods to estimate each individual’s exposure over the full work shift. We did not examine the chemical makeup of the dust collected. Viable fungi were measured using several 5-minute area samples in various locations throughout the store. Both chronic and acute symptoms were evaluated using standardized, interviewer-administered questionnaires. A total of 270 tests were conducted among 226 employees. 1.2 Personal and area monitoring results Average dust levels were 0.21 mg/m3 and below the current WBC exposure limits of 4 mg/m3 for amorphous silica and 10 mg/m3 for dust \"not otherwise classified\". This level is approximately the same as that found for office-based employees in the lumber and grain industries and within non- dusty areas in lumber mills. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 6 of 76 Endotoxin was extracted from the personal dust samples. Average endotoxin levels were 0.75 ng/m3. These levels were higher than outdoor samples (indicating the presence of an indoor source) but lower than a recently proposed health-based exposure limit of 20 ng/m3. Most of the variability in both dust and endotoxin exposures was unaccounted for by the factors we studied. Neither dust nor endotoxin levels were specifically associated with glass breaker operation. Exposure to both was significantly higher among employees who spent more time in the back section of the stores, closer to glass breaking machines or whole glass recycling activities (regardless of whether or not the glass breaking machines were operating). A total of 622 fungal samples were obtained. Viable fungal exposures ranged from less than detectable to over 18,000 CFU/m3 (the upper limit given the method used here), with an overall average of 1791 CFU/m3. This is above the Health Canada investigational guideline for office buildings (500 CFU/m3) suggesting that an investigation of a building related source is warranted. Viable fungal counts were clearly associated with glass recycling activities (highest around broken bottles, next highest elsewhere in the warehouse, lowest at the cashier station). The most important single factor associated with increased viable fungal counts was whether moldy bottles were being broken in the store (either mechanically or manually) on the test day. Fungal counts were higher in stores with rotary conveyor and rotary hydraulic glass breaking machines and stores with outdoor empties return kiosks. This increase may be related to the increased volume of returns handled by these stores. Fungal counts were also higher in stores where glass bins were uncovered. Fungal counts were not obviously lower on days when the glass breaking equipment was not operating. It would appear therefore, that glass recycling as a whole is contributing to fungal counts, regardless of whether the glass breaking machines were operating or not. 1.3 Symptoms and their relationship to exposures Overall, LDB employees reported more chronic chest tightness (31% v. 17%) and nasal symptoms (61% v. 49%) than ‘expected’ based on comparison with a group of BC Ferry Corporation Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 7 of 76 employees. For ‘work-related’ symptoms, the relative risk for LDB employees was even greater compared to ‘expected’ (4.8 times higher for chest tightness, 2.9 times higher for nasal symptoms, and 2.5 times higher for eye irritation). For acute symptoms occurring more than once in the past week, 20% of LDB employees reported 2 or more symptoms relating to nose or throat irritation (including voice or taste disturbances), 16% reported two or more chest symptoms (cough, wheeze, chest tightness, breathlessness), 25% reported eye irritation, 11% reported skin irritation, 11% reported 2 or more somatic symptoms (headache, tiredness, nausea, dizziness, fever) and 6% reported nosebleeds. There was no clear relationship between symptoms and operating glass breaking machines. However there were significant associations between some acute symptoms and specific exposures and work practices. Increased nasal and throat irritation in the past week was significantly associated with increased dust exposure (greater than 2 fold increase). Increased chest symptoms in the past week were significantly associated with the most important ‘surrogate’ measure of fungal contamination, namely, visually contaminated bottles being broken in the store (2½ fold increase). These relationships were seen regardless of whether or not the glass breaking machines were operating. None of the acute symptoms was associated with endotoxin exposure, nor with measured fungal counts. For endotoxin, this is likely because exposures were well below levels believed to cause health effects. For fungi, this is more likely because the quantitative measure used in this study is only a crude measure of the biologically relevant fungal exposure. We found no evidence of a link between increased chronic symptoms and specific exposure levels or surrogate exposure markers. This finding suggests that the impact of glass recycling on health is either limited to acute effects, or that there has not been sufficient duration of glass recycling exposures to make an impact on chronic symptoms. It is not possible to distinguish between these two possibilities from this study. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 8 of 76 Finally, we found evidence that the psychosocial work environment was linked to some of the symptoms reported. Increased eye and skin irritation and somatic symptoms (e.g. headache, nausea, dizziness, fever, tiredness), were associated with increased job strain (i.e. relatively poorer balance between perceived psychological demands of work and individual control over work tasks) and reduced work satisfaction and poorer communication between management and workers. 1.4 Conclusions The investigation supports the following conclusions: As no relationship was demonstrated between operation of glass breaking machines and either symptoms or measured levels of dust, endotoxin, or viable fungi, it is not clear that halting the glass breaking but continuing recycling would reduce exposures or symptoms. There is some evidence that the presence of recycled materials in the stores is associated with an increase in fungal levels. There is stronger evidence that an important contributor to fungal levels was whether or not visually contaminated bottles were being broken in the store (either mechanically or manually). Removal or redesign of the recycling operations in LDB stores may reduce fungal exposures and could have a positive effect on symptoms. There is some evidence that dust exposures in LDB stores is associated with an increase in acute irritation of the nose and throat. The source of the dust is not clear. Results suggest that the dust measured may be combination of outdoor dust being brought indoors, dust from stocking shelves and dust from the glass breaking operations, but no analyses were carried out to examine the chemical makeup of the dust collected. Improved dust control measures may have a positive effect on these symptoms. Attention to improving the psychosocial dimensions of the work environment may also have a positive impact on some symptoms. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 9 of 76 2 Introduction This report presents results of a study undertaken to investigate exposures to airborne particulate matter or ‘dust’, viable fungi, and endotoxin, and reported symptoms, in BC Liquor stores. The project was motivated by employee concerns about possible health problems linked to the installation of glass breaking equipment as part of a recently augmented glass recycling program. The overall objective of the study was to assess the impact of bottle recycling operations in general, and glass breaking in particular, on concentrations of inhalable particulate matter, viable fungi and endotoxin present in retail stores; and on the prevalence of acute and chronic symptoms among employees in these stores. A search of the health literature revealed no information about the potential health impact on employees of exposures associated with beverage container recycling, although there is a growing literature documenting adverse health effects of bioaerosol exposures in more complex recycling operations (such as for municipal waste).(1-3) In British Columbia, approximately 2500 employees work in retail outlets in which glass breaking equipment has been installed. The number of Canadian workers who may be similarly exposed now or in the future is not known. The protocol for the study was developed by the UBC researchers in consultation with a Project Advisory Committee made up of representatives of the Liquor Distribution Branch (LDB) management, the BC Government Employees’ Union (BCGEU), and the BC Workers’ Compensation Board (WCB). The Advisory Committee approved the protocol prior to the commencement of testing. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 10 of 76 3 Background In response to concern about environmental pollution, glass recycling programs have emerged in many Canadian communities. In British Columbia, one such program enables liquor store customers to return all beverage alcohol containers purchased from these outlets for refund. In 1998, the British Columbia Liquor Distribution Branch (BCLDB) expanded their beverage container recycling program to include wine and spirit containers. Domestic beer bottles and cans are recycled mainly by the brewers (and therefore stored and shipped back to them whole). Imported beer bottles, glass wine bottles, and spirits containers cannot be reused. They are processed and recycled into building and other materials. In order to increase the weight: volume ratio of bottles (i.e., to facilitate storage and shipping), 183 of the 223 year-round outlets in the province are equipped with glass bottle breaking machines (Rotary Inc., New Westminster, BC; Glass Aggregate, Minnesota, USA) which can reduce glass volume approximately 3 fold. Bottles are fed into the breakers, either directly or via a hopper or conveyor, and shattered by rotating hammer-like metal 'teeth'. Fragments fall into a large plastic storage bin underneath, otherwise covered with a fitted, hinged lid to prevent glass particles from being ejected. In most cases, the broken glass accumulates in the bins in a conical pile which, when high enough, may back up into the breaker mechanism and cause an equipment malfunction. In order to prevent this, workers periodically lift up one side of the hinged lid and use a rake to spread the glass more uniformly within the bin, thereby \"flattening\" the pile and allowing more glass fragments to fit inside before a bin change is required. The three most common glass breaker configurations include the rotary single-feed (61 stores), rotary conveyor (35 stores), and glass aggregate machines (85 stores). One busy Vancouver store is equipped with a higher-throughput, hydraulic rotary conveyor breaker to manage higher volumes of customer returns. That machine type, as well as the glass aggregate breaker, does not require raking, as the glass fragments are strewn into the bins more evenly due to their differing operational characteristics. Finally, one other store is equipped with a barrel rotary single feed (although not selected as a test site in this study). Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 11 of 76 Once bins are filled, they are covered and stacked in the warehouse until the next scheduled liquor delivery, at which time they are exchanged for empty ones along with the new stock. Frequency of bin exchange varies from as little as once to 4-5 times per week, depending on the volume of sales and empty containers for each store. Shortly after the glass breakers were installed in the stores, employees began reporting symptoms such as upper airway and dermal irritation, headaches, nosebleeds, and other respiratory complaints. In order to address these concerns, and minimize the amount of material ejected to the store environment, a dust collection unit was retrofitted to each machine in 1999. Each unit consisted of fibre filter bags and exhaust fan, drawing directly from the glass collection bins and vented to the outdoors. Despite the introduction of local exhaust systems in all stores with glass breaking equipment, employee complaints have persisted. Therefore, in summer 2000, the LDB and the BCGEU approached the UBC School of Occupational and Environmental Hygiene for assistance with developing a research project to further investigate the relationship between employee health and exposures associated with the recycling operations. This led to the development of a draft research protocol and the formation of a project advisory committee (with representation from the LDB, the BCGEU and the WCB). The project had the following specific aims: 1. to select a sample of 36 stores for study, using a stratified random sampling scheme; 2. to measure average full-shift airborne exposure to inhalable particulate matter and bacterial endotoxin for employees in each store, using personal sampling; with and without glass breaking machines in operation; 3. to measure airborne exposure to moulds at several locations in each store, using area sampling, with and without glass breaking machines in operation; 4. to record acute respiratory, mucous membrane, skin, and other symptoms among employees of each store, with and without glass breaking machines in operation, using a standardized questionnaire; Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 12 of 76 5. to record chronic symptoms, demographic characteristics, and health and lifestyle history information on employees of each store on one occasion, using a standardized questionnaire; 6. to compare the results of personal and area monitoring and symptom assessment, to determine whether there is a relationship between contaminants present in the workplace environment and symptoms; and to evaluate other possible risk factors for differences in symptom rates; and 7. to make recommendations on abatement measures, if necessary. The objectives and protocol were approved by the project advisory committee. Funding for the project was provided to UBC by the Prevention Division of the Workers' Compensation Board. Fieldwork commenced in mid August, 2000 and finished at the end of February 2001. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 13 of 76 4 Methods 4.1 Study design and general protocol 4.1.1 Selection of study sites A total of 36 retail liquor stores (out of the total of 223 year round outlets) were chosen for inclusion in the study according the following protocol. A stratified random sample of 34 stores was drawn from three areas of the province: the Vancouver and BC lower mainland area, Victoria and surrounding area, and the rest of the province (17, 12 and 5 stores, respectively). The number of stores drawn from each region was determined by the advisory committee in advance. Randomization was based on store numbers, using the random function in Microsoft Excel . In addition, two stores from the lower mainland region were nominated for inclusion (one each by the BBCGEU and LDB management) for a total of 36 sites. A single crossover intervention design was used. Two visits were scheduled for each store. After the baseline visit to all stores, the investigators selected half the stores, at random, to have their glass breaking operations shut down for at least one month, leading up to the follow-up visit. One store selected (a nominated store) was unable to comply with the 'shut down' request, thus reducing the number of stores in the 'breaker shut down' arm of the study to 17. Repeat testing visits were scheduled on random days during the week following the 4th 'shut down' week. The remaining stores continued their glass breaking operations for the duration of the study. Stores in which the glass breaker was thus shut down still accepted customer container returns, but placed them manually in plastic bags or the plastic bins normally used with the breaker to collect and store broken glass. Full bins and bags were exchanged for empty ones in the usual manner for the shutdown stores, although more bins and bags were required in the warehouses to accommodate the unbroken bottles. The other stores proceeded with normal glass breaking operations leading up to their follow-up visit. Therefore, this study only directly evaluated the effect of the glass-breaking operation and not the entire recycling program. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 14 of 76 4.1.2 Notification of stores for sampling visits Only the UBC researchers knew the identity of stores chosen for sampling. Each store was contacted, by fax and then telephone, at approximately 13:00h the day before the visit, to inform the store manager and employees that a researcher would arrive at an agreed upon time the following day. LDB management and the BCGEU were notified of the sampling site at the same time as the store itself was notified. The 1/2 day advance notice was useful to allow the UBC hygienist to determine the number of staff and their shift start times, and allow the LDB manager to ensure adequate staff coverage in the store for the testing period (approximately 9:00h to 18:00h; or 12:00h to 21:00h). 4.1.3 Participant Recruitment Prior to any testing, every LDB employee received a letter outlining the aims of the study and explaining that all employees working in a store chosen for sampling would be eligible and encouraged to participate. Participation was voluntary. Each study participant signed a ‘consent to participate’ form (Appendix 1) prior to testing, after having the aims and objectives of the study explained. At each store, employees were considered eligible to participate if they were on shift for a minimum of 4h within the sampling period. A maximum of 6 employees could be tested per day, due to equipment availability. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 15 of 76 4.1.4 Confidentiality Participation in the study was voluntary and participants were free to withdraw from the study or any aspect of the study at any time. No results that identify individuals will be released at any time. All testing procedures were approved prior to the commencement of the study by the UBC Clinical Screening Committee for Studies involving Human Subjects. 4.2 Personal and Area Monitoring 4.2.1 Introduction Monitoring was conducted for inhalable particulate matter (dust), airborne bacterial endotoxin, and airborne viable fungi. Inhalable particulate refers to dust particles of the size that can be readily breathed in and deposited on both upper and lower air passages (i.e. in the nose, throat, and lungs). Inhalable dust was monitored as an indicator of airborne glass particles, although all airborne particles and not just glass are captured by the method. Airborne endotoxin and viable fungi (or mould) are biological agents commonly associated with contaminated water or organic materials. As beer and wine residue can support microbiological growth, these common contaminants were chosen as markers of the potential for bioaerosol exposures. Endotoxin is a toxic component of the cell walls of bacteria, commonly found wherever there is a possibility of bacterial contamination. High levels of both endotoxin and fungal exposure has been linked to a variety of symptoms including eye, nose, chest and skin irritation, fever, and headache.(4-6) Full details of the monitoring protocols are contained in Appendix 2. A brief summary is provided here. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 16 of 76 4.2.2 Inhalable particulate matter/ endotoxin sampling Each employee who agreed to participate was outfitted with a portable sampling pump connected to an air sampler (with filter) clipped to the lapel. This configuration positions the sampling device within the person's breathing zone. The pump was worn for the full duration of the employee's work shift (ranging from a low of 4 hours to a high of 8.5 hours, with an average of 5.7 hours). The sample filter was weighed before and after sampling to obtain a measure of the concentration of inhalable particulate (dust) averaged over the entire work shift. This method provides the best estimate of each person’s exposure over a full day's work in all locations in the store. After weighing the filter in a temperature and humidity controlled laboratory, each dust filter was subjected to chemical extraction for endotoxin analysis. As the endotoxin measurement comes directly from the dust collected on the filter, the endotoxin results also reflect each person’s full work shift exposure to endotoxin in the air. In addition to the personal dust sampling, one stationary sampler/ pump combination was set up outdoors near each store. The sample location was generally in the loading dock area, located away from the building and local exhaust outlets. The average outdoor sampling time was 5.9 hrs, similar to the average sampling time for store employees. A total of 270 usable personal samples and 71 outdoor samples were obtained. 4.2.3 Viable fungal sampling Airborne viable fungi were measured using short duration stationary samples (sampling onto a culture plate located on a tripod) in various parts of the store and the immediate outdoor environment. Stationary sampling is required for fungi as there is no practical personal sampling method available for large numbers of fungal samples. The samples are short duration in order to prevent overloading the culture plate. The limitation of this method is that it captures only a brief 'snapshot' of exposure and does not provide as good an estimate of the exposure that an individual employee would experience over the full workday. To reduce the effect of this limitation, 7-10 samples (5 minutes duration each) were collected at different locations in each store on each testing Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 17 of 76 visit. Locations were chosen to represent the different working areas in the store environment. These included: near the breaker (operating and non-operating); elsewhere in the warehouse (not close to the glass breaker or empties bins); at the cashier station; and at the empty returns counter. When possible, samples were taken just prior to and just after the glass in the bin was raked. Outdoor samples were also taken in order to investigate seasonal trends and to provide a basis of comparison for indoor samples. This method also only captures viable spores (those that can be cultured) while both viable and non-viable spores may be associated with health symptoms. It was intended that one sample be taken 5 min before and after raking events at each visit. However, it was not always possible to do so, for several reasons: the store's use of a glass aggregate machine, which generally did not require raking; no raking taking place during the sample period; or very sporadic raking activity during the period that took place while the hygienist was interviewing employees. Where pre- and post-rake samples were not taken, additional samples were taken near the empties return counter to approximate potential exposures to workers receiving the containers. Plates were returned as soon as possible to the SOEH laboratory and incubated at room temperature for 7 days on a lab bench with exposure to natural lighting. Visual counts (for total colony forming units) and a qualitative assessment of the main fungal species present were made with the aid of a stereo microscope. The microbial ecology of the samples was evaluated by determining the identities of the predominant fungal genera. In previous studies conducted in British Columbia and including all seasons, the predominant fungal genera isolated from outdoor air are, in rank order, sterile mycelia (including Basidiomycetes), Cladosporium, yeast, Penicillium, Aureobasidium, and Botrytis. The normal habitat of Cladosporium is the surface of foliage (phylloplane) and in temperate regions can be found in abundance in outdoor air samples all year. In contrast, the microbial ecology of fungi found in other environments will vary with the amount of available moisture or nutrient sources. In this study, indoor and outdoor samples were compared and the predominant fungal genera were ranked. The outdoor samples were predominantly composed of Cladosporium or other phylloplane fungi, while typical indoor samples were predominantly composed of Penicillium spp. The source of Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 18 of 76 fungal colonies was assigned as “outdoor” or “indoor” based on clear differentiation of ranked genera. 4.2.4 Collection of data regarding the store environment At each store visit, the hygienist completed a standard form (see Appendix 1) to gather information on store or visit-specific factors that may be relevant to the assessment of exposures or health. These factors are listed in table 1 below: Table 1: Store environment factors FACTOR INFORMATION RECORDED store staffing • total number of employees on shift ambient conditions • indoor relative humidity • indoor and outdoor temperature • median household income of the neighbourhood cleaning activities • date floors last cleaned • date glass breaker last pressure washed store layout • visual estimate of crowding in warehouse (4 categories) • approximate warehouse size (4 categories) • location of glass breaker relative to empties counter • outdoor empties return location (yes /no) • location of store (in mall, free standing, below grade) ventilation (where possible): • main duct/ bin hose flows, discharge locations glass breaking volumes • number of glass bins filled • number of can bins filled • number of bin changes • volume of returns (wine/spirits; beer), previous month machine type and activities related to breaking • machine type (glass aggregate, rotary single feed, rotary conveyor, rotary conveyor - hydraulic) • number of times raking occurred • number of times jams were cleared • visually contaminated bottles routinely put through the breaker (yes/no) • use of spray cleaner for glass breaker (yes/no, and number of times) • use of local exhaust (seldom or never, when breaking glass only, always) • bins covered (yes/no) • empties bins stored in the store the previous night (yes/no) Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 19 of 76 4.3 Symptom Assessment Each participant was interviewed using two standardized questionnaires to assess acute and chronic symptoms. On each sampling day, each participant completed a short 2 page interviewer-facilitated questionnaire that enquired about acute symptoms experienced in the past week. In addition, each participant completed a longer health and employment questionnaire. The health portion of this longer questionnaire is an expanded version of the American Thoracic Society standardized questionnaire recommended for use in epidemiologic surveys.(7) A detailed work and job history was included to account for jobs both within and prior to work with the LDB. A standardized series of questions was included (Karasek Job Control - Job Demands instrument)(8) to evaluate each employees assessment of the psychosocial aspects of their work, including job satisfaction, job demands and control over work tasks. Questionnaires were administered by a trained interviewer, and were conducted during the work shift. For four participants, the interviewer lacked sufficient time to complete the longer questionnaire on the day sampling took place, requiring the longer interview to be conducted over the phone. Copies of these questionnaires are included in Appendix 1. 4.4 Data management and analysis 4.4.1 Definitions For purposes of data analysis, the questionnaire items were coded and categorized following standard definitions for demographic and health outcomes. The definitions for all variables used in this report are contained in Appendix 3. Briefly, definitions for chronic symptoms were those recommended by the American Thoracic Society for epidemiologic studies of respiratory disease.(7) Any uncertainty in responding to a questionnaire item was recorded as a negative response. Work-related symptoms were those not Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 20 of 76 present prior to starting work with the current employer, and which either improved on holidays and weekends, or which were aggravated by workplace exposures. Acute symptoms were recorded as present only if the respondent reported the symptom occurring more than once during the previous week. 4.4.2 Data verification Information recorded on the questionnaire and store data forms was coded and checked at least two times for errors, before and after coding. Questionnaire data was entered into computer files by professional data entry personnel, verified by double entry, and subsequently checked for transcription errors and omissions. Filter sampling data was first transferred from the field logs and forms into Excel spreadsheets and ASCII text before being read into SAS®. All air sampling and questionnaire data were analyzed using SAS® software, with edit, data checking and analysis programs written by the UBC research team. 4.4.3 Comparison group Some of the results from this study were compared with results from a similar study carried out by the same research team, using the same chronic symptoms questionnaire, among employees of the BC Ferry Corporation. The comparison group chosen for the current analysis included BC Ferry employees working in catering, passenger service, traffic control, and deck crew (tested in1999). The comparison was only possible for the chronic symptoms as the assessment of acute symptoms was not carried out in the BC Ferries study. 4.4.4 Data analysis In addition to descriptive statistics regarding the store and work environments, measured exposures, and symptom responses, the main data analysis involved a series of comparisons designed to evaluate the impact of glass recycling operations on the levels of airborne contaminants and the relationship with health symptoms. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 21 of 76 • Levels and the number of measurements above defined high cut-offs were compared between the two visit 2 groups (with machines shut down and without) to evaluate the impact of glass breaker shutdown on air contaminants (Section 6.2). • Store environment and work activities were analyzed in relation to measured exposures to assess what factors contribute to high or low concentrations (Section 6.5). • Chronic symptom responses from the entire LDB employee study group were compared to a reference study population to evaluate the level of long-term health symptoms reported in this group of workers (Section 7). • Acute symptom responses, for both individual symptoms and groups of similar symptoms, between visit 1 and visit 2 and between the two visit 2 groups were compared to evaluate the impact of glass breaker shutdown on contaminant levels (Section 8). • Acute symptom responses were compared between concentrations that were above and below pre-defined high cutoff levels, while also considering other factors that may have affected symptom responses (Section 8). Descriptive analyses for dust, endotoxin, and viable fungi involved examination of frequency distributions, means, ranges, and measures of variability for all results together and then for results, stratified by visit and study arm. As the sampling data followed lognormal distributions, geometric means and variances were calculated (based on log, base e transformations) in addition to arithmetic means and variances. More detailed analyses of store environment characteristics associated with contaminant levels were also carried out, first with univariate analyses, followed by multiple regression \"determinants of exposure\" modeling. For this regression modeling, the dependent variables (or outcomes) were the dust, endotoxin, or viable fungi levels (3 different models) and the independent variables included all the store and activity variables collected during the field study. This are listed in the methods section, above, and described in detail in Appendix 3. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 22 of 76 Similarly, univariate comparison of symptom prevalence rates were carried out with demographic, personal history, and work environment factors (including specific exposure levels for each of dust, endotoxin, and viable fungi). This was followed by multivariable analyses, using multiple logistic regression modeling. Factors were only considered for inclusion in the multivariable models if they were associated with the exposure in univariate analysis with p < 0.20. Highly correlated explanatory factors were grouped and analysed separately. Only the most informative variable from among a group of highly correlated variables was offered in the final multiple regression models. Variables were offered to the model in meaningful groups starting with those expected to be linked to the outcome based on theory or previous evidence. Model 'fit' was evaluated based on adjusted R2 values (linear regression models) and likelihood ratios (logistic regression models). Further information on the application of these analysis strategies is included in the relevant sections of the report. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 23 of 76 5 Results: Sites and participants 5.1 Participation Out of a potential 318 eligible personnel, 272 were sampled from the 2 visits, giving an overall participation rate of 86%. This is a high rate of participation for a study of this type, and indicates that the results are not likely to be biased because of poor participation. Table 2: Participation summary Visit Region number eligible to participate number who did participate participation rate average participation rate, by visit 1 Vancouver area 96 84 88% Victoria area 54 43 80% 86% Elsewhere in BC 19 19 100% 2 Vancouver area 92 74 80% Victoria area 41 36 88% 85% Elsewhere in BC 16 16 100% total 318 272 86% 5.2 Sites included compared to those not included Although the stores to be studied were selected at random from all stores in three specified regions (greater Vancouver, greater Victoria, and the rest of BC), the proportion of stores selected from each area differed (as decided by the project advisory committee). In total, we studied 23% of stores in the greater Vancouver area, 67% of stores in the Victoria area, and only 6% of stores in the rest of the province (Table 3). In order to evaluate the possibility that store characteristics varied across the 3 selection regions, and to examine the possibility that the stores selected differed systematically from those not selected (despite the random selection), we examined store characteristics available to us, comparing stores included to stores not included. These results are shown in Table 3 below, stratified by the sample selection regions. The information in the table is based on August 2000 data, provided by LDB management. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 24 of 76 Table 3: Comparison of study sites to all BC liquor stores Vancouver area Victoria area Other BC studied not studied p1 studied not studied p1 studied not studied p1 p2 n (% of total studied) 19 (23%) 65 12 (67%) 6 5 (6%) 76 machine type rotary single feed rotary conveyor glass aggregate other 47% 26% 21% 5% 62% 29% 9% 0 ns 75% 17% 8% 0 50% 33% 17% 0 ns 0 0 100% 0 0 9% 89% 1% ns <0.001 number of employees (FTE)/store, ave. (sd) 12.1(5.1) 12.8(6.0) ns 11.4 (6.4) 12.2 (6.2) ns 8.9 (3.7) 6.0 (4.5) ns <0.001 volume of returns2 wine / spirits (ave.) beer (dozens) (ave.) 17,674 10,010 18,255 9,676 ns ns 21,116 10,289 13,114 9,969 ns ns 9,364 8,935 4,772 4,540 ns ns <0.001 <0.001 1. comparing values in the stores tested to those not tested 2. comparing values across the three regions In this table, and in the other tables that follow, the notation ‘p’ refers to the probability (associated with the appropriate statistical test) that there is no difference between the groups being compared. Thus, a low ‘p’ value indicates that the groups most likely are different. It is common to accept that ‘p’ values smaller than 0.05 are sufficient evidence of statistically significant differences. Put another way, ‘p < 0.05’ indicates that the probability that the groups are the same is less than 5% (one chance in 20) and ‘p<0.001’ the probability that the groups are the same is less than 0.1% (one chance in 1000). The notation ‘ns’ in the tables stands for ‘not significant’ and indicates that the ‘p’ value is greater than 0.05. Within the three selection regions, there were no significant differences between the stores selected and those not selected. Although there appears to be a trend to higher return volumes in the selected stores in Victoria and the rest of BC, these differences are based on relatively small numbers of stores and were not statistically significant. However, there are significant differences in store characteristics across the regions. Stores outside the Vancouver and Victoria areas have fewer employees and handle fewer bottle returns. Almost all the stores in these areas are equipped with glass aggregate bottle breaking machines, whereas about 80% of Vancouver and Victoria stores are equipped with rotary glass breaking machines, either fed manually (single feed) or via a conveyor. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 25 of 76 5.3 Store characteristics: environment, equipment, and procedures The selection of stores to have the glass breaker shut down between visits was carried out at random, to reduce the chance of systematic differences in the 2 groups of stores. To confirm this, after the survey was completed, we examined whether or not significant differences existed in the store characteristics according to their ‘shut-down’ category. This comparison is shown below. Table 4: Store characteristics, by study group regular operation glass breaker will be shut down p1 number 19 17 number of employees (FTE’s) 12.2 (5.4) 10.5 (5.3) ns warehouse size small medium large very large 16% 26% 53% 5% 24% 41% 35% 0 ns crowding wide open not crowded crowded very crowded 42% 21% 32% 5% 41% 12% 47% 0 ns machine type rotary single feed rotary conveyor glass aggregate other 53% 21% 21% 5% 47% 18% 35% 0 ns location of empties returns counter and breaker close together separated by conveyor / wall glass breaker far from returns counter 63% 16% 21% 100% 0 0 <0.05 outdoor empties return kiosk 16% 6% ns median family income in neighbourhood $43K $44K ns 1: p values, comparing stores not selected for breaker shut down to stores selected for breaker shut down There were no differences between the 2 groups of stores with respect to number of employees, approximate warehouse size and crowding, or type of glass breaking machines. By chance, there was a significant difference between the 2 groups in the location of the glass breaker. The glass breaker was separated from the counter by a wall or by distance in 37% of stores in which normal operations would proceed, whereas in the stores in which the breakers would be shut down in phase 2, all the breakers were located adjacent to the empties counter. This feature was used to advantage in the visit 2 testing. In the stores in which the breaker was not operating, the fungal sampler was placed on the empties counter, just adjacent to the (non-operating) glass breaker. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 26 of 76 We also examined site and day specific store environment and bottle recycling activities on the testing day, stratifying the stores according to their study group (e.g. stores with regular operations between visit 1 and visit 2, v. stores in which the glass breaker was shut down between visit 1 and visit 2) and visit. These results are shown in Table 5 below. Table 5: Store environment characteristics and recycling activities, by visit, group Visit 1 p1 Visit 2 p1 p2 regular operations regular operations, but glass breaker will be shut regular operations glass breaker shut down number 19 17 19 17 outdoor temperature, oC 15.3 15.2 ns 7.3 7.5 ns <0.01 indoor temperature, oC 18.6 18.7 ns 17.1 16.4 ns <0.01 indoor relative humidity % 57.8% 57.0% ns 53.0% 54.5% ns ns indoor air water content (lb H2O/lb air) 0.0082 0.0081 ns 0.0067 0.0066 ns <0.01 returns volume (previous month) wine, spirits beer (dozens) 21,928 12,369 17,774 9,939 ns ns 22,040 10,129 16,588 7,894 ns ns ns ns number of bins filled glass bins actual number adjusted for non-broken bottles can bins 0.76 0.76 1.85 0.64 0.64 1.49 ns ns ns 0.66 0.66 1.59 1.15 0.39 1.31 0.05 <0.05 ns ns 0.07 ns empties stored overnight (% yes) 5% 12% ns 16% 71% <0.001 <0.001 raking today (% yes) 74% 59% ns 63% 0 <0.001 <0.01 jams cleared today (%yes) 26% 0 <0.05 5% 0 ns ns contaminated bottles in breaker, or broken manually (% yes) 73% 63% ns 46% 7% <0.001 <0.001 glass bin covered (% yes) 100% 100% ns 95% 6% <0.001 <0.001 local exhaust on all day on during /after breaking used rarely or never 32% 63% 5% 35% 59% 6% ns 53% 42% 5% 6% 0 94% <0.001 <0.001 breaker washed, past mo. (%yes) 21% 18% ns 16% 12% ns ns days since floors were cleaned 3.1 3.1 ns 2.6 2.8 ns ns % of employee time spent: cashier, cust.service, office, stocking shelves empties returns / breaker liquor loads/orders 47.8% 17.5% 17.8% 16.8% 48.8% 14.7% 17.8% 18.7% ns ns ns ns 46.0% 15.2% 19.9% 18.7% 45.4% 13.6% 20.0% 21.1% ns ns ns ns ns ns ns ns % of employees spending > 50% of time in warehouse area 9% 18% ns 22% 25% ns <0.05 1. p values for comparisons between store operations groups, within visit 2. p values, comparing visit 1 to visit 2 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 27 of 76 Within visit 1, there were no significant differences in site specific activities or characteristics between the stores in the two arms of the study (shut down v. regular operations), except for a small difference in the proportion of stores in which bottle jams were cleared. Within visit 2 due to the shutdown of machines in half of the stores, differences were expected and were found for variables relating to the work changes in those stores in which the glass breakers had been shut down for the preceding month. For example, these stores were significantly more likely to have stored full glass bins in the warehouse overnight, and almost all of them had uncovered bins in the warehouse during the day. By definition, there was no broken glass raking being carried out in these stores, nor were contaminated bottles being broken by machine. The field researcher did note, however, that in one store, contaminated bottles were broken in the process of throwing them into the bin manually. These stores also tended to fill a greater number of bins, although when the number of bins was adjusted for the differential volume between broken and unbroken bottles (3:1, according to LDB management), it appeared that the actual number of bottle returns handed was somewhat lower in visit 2 in the ‘shut down’ stores compared to the other stores. These differences in the store environments and activities will need to be taken into consideration when interpreting both exposures and symptoms in stores in the two arms of the study. Comparing visit 2 to visit 1 (p-values shown in the last column of the Table), there were significant differences across all stores for ambient conditions (decreased outdoor and indoor temperature, and decreased water content of the indoor air), in activities in the warehouse area of the stores (empties more likely to be stored overnight, glass bins less likely to be covered, local exhaust systems used less frequently), in glass breaking activities (less raking, fewer stores in which contaminated bottles were put through the glass breakers), and in the time spent by employees in the warehouse (with a greater proportion of employees spending more than half their day in the warehouse areas at visit 2, regardless of whether or not the glass breaker was shut down). We also examined the relationships among the various store environment and activity factors. As would be expected, all the ‘glass breaking’ activities were strongly associated with each other. In addition, the volume of bottle returns varied according to machine type and according to whether or not the store had an outdoor return kiosk. Stores with glass aggregate machines handled the Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 28 of 76 fewest returns and those with rotary conveyor machines processed more returns. The one store with a rotary conveyor machine with hydraulic assist processed more than twice the number of wine and spirits bottles than other stores (Table 6). This finding suggests that will be difficult, in this study, to examine the influence of volume of returns separately from machine type. It also indicates that analyses to examine the influence of machine type will also need to take into account the presence (or not) of an outdoor kiosk and the volume of empties handled. Table 6: Volume of empties, by machine type and presence of outdoor kiosk Outdoor Kiosk: Machine Type glass aggregate rotary single feed rotary conveyor rotary conveyor hydraulic p1 no outdoor kiosk number of sites 9 15 7 1 beer returns, dozen (average) 6,545 7,689 10,679 19,676 <0.001 wine / spirits returns (average) 7,841 15,558 27,570 68,873 <0.001 number of can bins filled on test day 1.0 (0.7) 1.4 (0.5) 1.9 (0.6) 2.0 (0) <0.001 number, glass bin (equivalents) filled on test day 0.3 (0.2) 0.6 (0.3) 0.8 (0.3) 1.5 (0.7) <0.001 outdoor kiosk present number of sites 1 3 0 beer returns, dozen (average) 28,017** 22,874** wine / spirits returns (average) 23,287** 40,230** number of can bins filled on test day 4.0 (1.4)* 2.5 (0.8) number, glass bin equivalents filled on test day 0.8 (0.4)* 1.2 (0.6) 1. p values, comparing across machine types *p<0.05, ** p< 0.01, comparing stores with an outdoor kiosk to those without Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 29 of 76 6 Results: Dust, endotoxin and fungal levels 6.1 Summary results 6.1.1 Dust and endotoxin Of the 272 employees who agreed to participate in the dust and endotoxin exposure monitoring (44 of whom participated twice), a filter sample was obtained for 270 (99.2%). Of the 72 area dust samples set up, a sample was obtained for 71 (98.6%). Summary information for all filter samples is presented in Table 7 below. Personal inhalable particulate levels ranged from below the detection limit of the method to a high of 1.8 mg/m3, with a mean value of 0.21 mg/m3 of air breathed. Endotoxin ranged from below the detection limit to a high of 10.5 ng/m3 with a mean of 0.75 ng/m3. Table 7: Inhalable particulate sample results, averages based on individual filters. Sample type N average (SD) median MIN* MAX % below detection limit personal samples 270 0.21 (0.14) 0.18 <0.008 1.84 0.7% Dust, mg./m3 outdoor (area) samples 71 0.06 (0.04) 0.05 <0.008 0.16 7.0% personal samples 270 0.75 (1.26) 0.37 <0.02 10.5 1.5% Endotoxin, ng/m3 outdoor (area) samples 71 0.10 (0.29) 0.03 <0.02 2.4 46% * approximate detection limit (varies with volume of air sampled) Outdoor samples were lower than indoor personal samples for both dust and endotoxin, with almost half the outdoor endotoxin samples below the detection limit. The exposure distribution for endotoxin was 'skewed' by a small number of higher values. This is evident by comparing the average to the median value (or 50% percentile value), where the median value is considerably lower than the average. Therefore, for statistical testing, the log value was used, to prevent these few high values having an overly strong influence on the results of analyses. Actual or geometric mean values will be presented in the tables, for ease of interpretation. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 30 of 76 6.1.2 Viable fungi A total of 648 fungal samples were collected. Locations and sampling frequencies are presented in Table 8 below. In contrast to the personal sampling for dust and endotoxin, in which it is possible for some samples to be too low to be detected by the methods used, for viable fungal sampling, it is possible for some samples to be higher than can be accurately assessed with the method used. This is because the agar plate becomes overloaded with spores and it is not possible to count the number of individual colonies. In such cases, it is only possible to report that the concentration is known to be at least as high as the maximum value of counts. These samples are listed as ‘overloaded’, and were assigned the maximum value (18,000 CFU/m3) for analysis purposes. Overloaded samples tended to occur more frequently when taken near the glass breakers. Table 8: Viable fungal counts (CFU/m3), by sampling location Sample Location N average (SD)1 median MIN MAX % overload % mainly ‘outdoor’ species Cashier station 143 605 (1007)* 271 0 7600 19% Near breaker, while operating 64 3280 (5156)** 982 0 >18,000 6% 9% Near breaker, max 5 min, pre-rake 16 646 (536) 460 121 2186 2% Near breaker, max 5 min. post- rake 33 4359 (6441)** 1243 107 >18,000 12% 9% Near breaker, not operating 22 2855 (5393)* 757 93 >18,000 9% 18% At empties counter 64 2037 (3476)* 590 29 >18,000 2% 6% Warehouse, away from breaker 139 1565 (3003)* 543 19 >18,000 1% 9% Outdoors, near store 141 694 (846) 457 93 5471 96% Sample damaged or unusable 23 All indoor samples 481 1791 (3647)* 500 0 >18,000 3% 12% Store average values (n=72 store/visits) 1918 (2093) 982 102 8143 n/a n/a * p<0.05; ** p < 0.001, compared to outdoors Based on identification of specific fungal genera, almost all the outdoor samples (96%) reflected a typical ‘outdoor’ species mix. In contrast, the majority (>80%, in all locations) of samples taken Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 31 of 76 indoors appeared to reflect other sources, not simply a transfer of ‘outdoor’ spores into the building. The lowest average, median, and maximum concentration were measured outdoors, at the cashier station, and pre-raking, relative to other sample locations. Samples measured at the cashier station were slightly (and significantly) lower than outdoor samples. Samples measured at the empties counter, in the warehouse away from the breaker, and near the glass breaker when it was operating and post-raking were all significantly higher than outdoor samples and those at the cashier station. Overall store average values were computed for each visit. These ranged from 102 to 8143 CFU/m3, with a mean of the store average values of 1918 CFU/m3. The distribution of samples was highly skewed (median values considerably lower than average values), indicating the presence of a small number of very high samples influencing the mean values. This is typical of viable fungal sampling in all environments. In the tables and analyses that follow, fungal counts will be shown based on several different store/visit average values: 1. average of samples taken at the cashier station 2. average of samples taken in the warehouse area away from the glass breakers 3. average of samples taken directly around the glass breakers and the empties counter, and 4. average of all samples in the 'back' of the store (i.e. 2 and 3 above) Peak values in these areas will also be examined. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 32 of 76 6.1.3 Comparison exposure values In order to put these numbers in context, it is useful to compare these results to exposure limits recommended by various organizations and to exposure levels found in other BC workplaces. Permissible or recommended exposure limits Dust (inhalable particulate): Regulatory standards for particulate (dust) typically refer to dust composed of a single compound or arising mainly from one source (e.g. iron oxide dust, wood dust, grain dust). There is no specific regulatory standard in any jurisdiction for ‘glass dust’. As glass is primarily a non-crystalline silicate, the closest standard is that for amorphous (or non-crystalline) silica. The BC standard for amorphous silica dust exposure is 4 mg/m3 (based on a sampling method that captures a slightly different size fraction of particles). The BC WCB standard for non-specific dust (referred to as particulate, not otherwise classified) is 10 mg/m3. The Threshold Limit Value recommended by the American Conference of Governmental Industrial Hygienists (ACGIH) for amorphous silica (inhalable fraction - the same fraction as measured in this study) is 10 mg/m3. Endotoxin There are, as yet, no regulatory exposure limits for endotoxin in any jurisdiction, nor is there a recommended ACGIH exposure limit. The reason for this is that research on the health effects of endotoxin is relatively new and ‘dose-response’ evidence on which to base a standard has only emerged recently. Based on a recent review of existing literature, a recommended exposure limit has been proposed in the Netherlands of 20 ng/m3 (Dutch Expert Committee on Occupational Standards, 2001, D. Heederik, personal communication). The lowest occupational exposure level reported in anywhere the scientific literature associated with any adverse impact on health is 9 ng/m3.(9) Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 33 of 76 Viable fungi According to the ACGIH which is the primary organization proposing exposure limits in North America, a general standard for culturable or countable bioaerosols (e.g. fungal spores, viable fungi or bacteria) is not scientifically supportable at this time.(10) The reasons for this all relate to the fact that although the total number of viable organisms is relatively easy to count, this measure provides only a crude indication of the biologically relevant exposure. Adverse health effects have been shown in association with both viable and non-viable organisms and their constituents and products. Furthermore, different microorganisms have different health effects. There is still insufficient evidence to describe the ‘exposure-response’ relationships and therefore to recommend exposure limits. Health Canada has suggested guidelines to assist building operators and occupants in evaluating possible fungal contamination of indoor environments.(11) They suggest that a fungal concentration over 500 CFU/m3 indicates a possible building-related source that requires further investigation. More specifically values above 150 cfu/m3 may indicate a building related source especially if the species mixture does not represent outdoor air spores. These guidelines were based on a review of results from over 3000 4 - minute area samples taken in more than 110 federal government buildings between 1986 and 1995. Exposures in other BC worksites, measured by UBC: We have measured personal exposure levels to dust and endotoxin, and taken area samples for viable fungi in lumber mills and grain elevators in BC using similar methods to those used in this study. These measurements have included employees working in ‘clean’ control rooms or offices and employees in visibly dusty areas. Average values and ranges are shown below. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 34 of 76 Table 9: Comparison exposure data from BC worksites site details inhalable dust mg/m3 mean (range) personal samples endotoxin ng/m3 mean (range) personal samples viable fungi CFU/m3 mean (range) area samples lumber mill mill office not measured not measured 153 (14 –439) log receiving end of the mill 0.68 (<0.03-1.88) not measured 16,626 (156 – 111,400) lumber planing dept. 2.61 (0.15- 9.36) not measured 876 (134 – 2,651) grain elevator * control room / office 0.18 (<0.06 – 0.46) 0.9 (0.2 – 7.8) not measured labourer/sweeper 3.85 (0.6 – 46.6) 1213 (0.2 – 15,600) not measured supervisor / foreman 0.40 (<0.06 – 2.4) 22.5 (0.2 – 387) not measured LDB study all samples 0.21(<0.008 – 1.84) 0.75 (<0.02 – 10.5) 1791(0 - > 18,000) * dust sampling reflects slightly different particle size range (called ‘total’ dust) that yields somewhat lower values than those for inhalable dust 6.1.4 Exposure categories For some analyses, we divided exposures into categories to reflect 'lower' and 'higher' exposure groups. The category cut-points were chosen to ensure that a sufficient number of participants in the study would fall into the 'higher' exposure group, while, at the same time, attempting to choose meaningful cut-points (either from a biologic or regulatory perspective). For dust, the exposure cut-point chosen was 0.2 mg/m3. This cut-point was close to the median value of the data obtained. For endotoxin, as all but a very small number of the exposure levels were well below values believed to be harmful in any previous studies, we chose an arbitrary cut- point of 1 ng/m3, the 80th percentile value. For viable fungal concentrations, we chose a cut-point (based on the average values in the 'back' of the stores) of 3000 CFU/m3. This cut-point is well above the upper 95% percentile for the outdoor and cashier station values (i.e. 2000 CFU/m3) and is approximately equal to the upper quartile of the store average values. Other cut-points were considered but none of the results that follow differed when analyses were repeated using different cut-points for the exposure categories. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 35 of 76 6.2 Airborne contaminant levels, according to visit, study group To examine if contaminant levels differed when the glass breakers were not operating, we evaluated the levels of these contaminants by visit and glass breaker operation status (Table 10). For these analyses, we compared average values as well as the proportion of samples in the 'higher' exposure categories (described above). Table 10: Dust, Endotoxin, and Viable Fungal levels, by visit and study arm Visit 1 p1 Visit 2 p1 p2 regular operations regular operations, but glass breaker will be shut regular operations glass breaker shut down number of stores 19 17 19 17 number of filter samples 78 66 67 59 DUST, outdoors (mg/m3) 0.048 0.049 ns 0.067 0.072 ns <0.05 mean of store averages 0.184 0.182 ns 0.222 0.218 ns 0.06 mean of all samples 0.187 0.196 ns 0.235 0.218 ns <0.05 DUST, personal (mg/m3) % >0.2 mg/m3 34.6% 36.4% ns 46.3% 54.2% ns <0.05 ENDOTOXIN, outdoors (ng/m3) 0.05 0.06 ns 0.19 0.08 ns ns mean of store averages 0.54 0.55 ns 0.83 1.04 ns <0.05 average of all samples 0.52 0.57 ns 0.88 1.13 ns <0.05 ENDOTOXIN, personal (ng/m3) % > 1 ng/m3 10.3% 15.2% ns 28.4% 20.5% ns <.001 FUNGI, outdoors (CFU/m3) 868 751 ns 485 667 ns <0.05 FUNGI area samples (CFU/m3) mean of store averages at checkout in warehouse3 near breaker/ec4 831 2123 4522 629 1529 5407 ns ns ns 506 1042 878 694 1634 1812 ns ns ns 0.06 <0.05 <0.001 mean, store peaks at checkout in warehouse near breaker/ec 1105 3182 7127 718 2140 8465 ns ns ns 727 1551 1531 947 1816 2631 ns ns ns ns 0.07 <0.001 % > 3000 CFU5 16.4% 14.6% ns 5.3% 9.7% ns <0.001 1. comparing glass breaker operational groups, comparing log (values) for endotoxin and fungal counts 2. comparing visit 1 to visit 2 3. samples taken in warehouse, away from breaker 4. all samples taken near the breaker and/or empties counter 5 % of total samples taken (n=622) Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 36 of 76 For ease of viewing, values significantly higher (p<0.05) in one or the other visit are indicated in bold. Average dust and endotoxin levels were significantly higher at visit 2 compared to visit 1 (p-values in the last column of Table 9), and store average values were higher in 24 of the 35 stores for both contaminants (see Appendix 4 for figures showing results for individual stores). There did not appear to be a relationship between either dust or endotoxin levels and operation of the glass breakers, with no significant differences in exposure levels comparing visit 2 results in stores where the glass breakers were still operating to those where the glass breakers were shut down. In contrast, viable fungal counts were significantly lower at visit 2 compared to visit 1, both indoors and outdoors. Similar to the results for dust and endotoxin, there was no difference in fungal counts at visit 2 in relation to glass breaker operation. 6.3 Seasonal trends Visit 1 testing spanned mid August to mid November, 2000 and visit 2, mid November 2002 to the end of February 2001. As outdoor fungal counts (and, in some studies, endotoxin levels) are known to follow seasonal trends, we examined monthly average exposures for possible seasonal trends in this study. Although dust levels did increase from visit 1 to visit 2, no seasonal trends were evident for dust or endotoxin (data not shown), but a trend was evident for fungal counts (Figure 1 below) across the study months. Both indoor and outdoor fungal levels declined over the study period. As evident in Figure 1, the difference between fungal levels in the back of the stores (in the warehouse, near the breakers, and at the empties counters) and either outdoor samples or samples at the cashier station was more pronounced in visit 1 compared to visit 2. This sharp drop in fungal levels in the back areas of the stores, from October forward, is consistent with a decrease in the water content of the indoor air (or absolute humidity), which is a function of both relative humidity and temperature (see Figure 2). Typically, in fall and winter, as the cooler outdoor air is warmed for indoor use, the water content drops considerably. Thus, we see an exaggeration of the outdoor seasonal trend in fungal counts, as the ability of fungal colonies to Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 37 of 76 proliferate is reduced in drier indoor environments in winter months. A similar, although less pronounced, trend (p=0.07) was seen for samples at the cash stations. The reason for the more exaggerated difference in fungal counts in the back of the stores (warehouse, empties counter, and glass breaker area samples) is not evident. It may be associated with increased artificial heating in the warehouse area (if the loading doors are more frequently open). This seasonal effect undoubtedly accounts for at least some of the difference in fungal levels between visit 1 and visit 2. Figure 1: Fungal levels by visit and month Figure 2: Ambient conditions, by visit and month Fungal counts (geo.mean) by visit and month 0 500 1000 1500 2000 Aug Sep Oct Nov Nov Dec Jan Feb visit 1 visit 2 C FU /m 3 indoor (back) outdoor cash Monthly trend in ambient air conditions 0 5 10 15 20 25 Aug Sep Oct Nov Nov Dec Jan Feb visit 1 visit 2 outdoor temperature indoor air water content (x10-3) Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 38 of 76 6.4 Regional differences in contaminant levels Monitoring results were also examined according to regions (6 regional categories provided by the LDB). Dust exposure levels in the Victoria region were significantly lower, on both visits, than levels in the rest of the regions studied (p<0.01). Average endotoxin levels did not differ by region. Fungal levels were significantly higher in stores in the Vancouver area compared to those on Vancouver Island and in the rest of the province (see below). It is possible that these regional differences in fungal counts may be linked more to seasonal effects than regional ones, as the Vancouver area stores were tested in August and September. The explanation for reduced dust and endotoxin levels in Victoria stores is not evident from these results. Figure 3: Contaminant levels by region Inhalable Dust, averages (ug/m3) 0 0.1 0.2 0.3 0.4 Va nc .Ea st Va nc .So uth Va nc .W es t Fra se r V all ey Ot he r B C Mi d I sla nd Vic tor ia visit 1 visit 2 Endotoxin, average (ng/m3) 0.0 0.5 1.0 1.5 2.0 Va nc .Ea st Va nc .So uth Va nc .W es t Fra se r V all ey Ot he r B C Mi d I sla nd Vic tor ia visit 1 visit 2 Viable fungi (in back of store) 0 500 1000 1500 2000 2500 3000 3500 4000 Vanc.East Vanc.South Vanc.West Fraser Valley Other BC Mid Island Victoria C FU / m 3 visit 1 visit 2 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 39 of 76 6.5 Work activities associated with fungal levels The strong seasonal difference in fungal counts across the two visits has the potential to obscure possible effects of change in the recycling activities on fungal levels. Therefore, we also analysed fungal counts in direct relation to specific recycling activities. In figures 4 and 5, below, we show average viable fungal counts taken at or near the glass breaker when it was operating (figure 4) compared to viable fungal counts from samples taken in the warehouse but far from the breaker. A similar comparison is shown in figure 5, but in this case we include all samples taken near the glass breakers or glass bins (whether or not the breaker was operating). This allows us to include samples taken near the glass bins on visit 2 in stores where the glass breaker was not operating. Figure 4: Viable fungal counts: samples taken near the glass breaker (when operating) compared to samples elsewhere in the warehouse, by region, visit 0 2000 4000 6000 8000 10000 12000 FV MI BC VE VS VW Vic FV MI BC VE VS VW Vic FV MI BC VE VS VW Vic FV MI BC VE VS VW Vic Regular operations Breaker to shut Regular operations Breaker shut down Visit 1 Visit 2 Breaker Operating Warehouse Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 40 of 76 Figure 5: Viable fungal counts: all samples near the breaker (operating and not), compared to samples taken in the warehouse (away from the breaker) These data show that fungal levels were higher in close proximity to the glass breakers and empties counters, compared to elsewhere in the warehouse, regardless of whether on not the glass breakers had been operating in the previous month. The increased fungal levels near the glass breakers and bins were most prominent during visit 1, when temperatures and indoor humidity were highest. No significant effect of breaker shutdown on the levels measured near the glass breaker or glass bins was evident. 0 2000 4000 6000 8000 10000 12000 14000 FV MI BC VE VS VW Vic FV MI BC VE VS VW Vic FV MI BC VE VS VW Vic FV MI BC VE VS VW Vic Regular operations Breaker to shut Regular operations Breaker shut down Visit 1 Visit 2 Breaker/EC (all samples) W arehouse Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 41 of 76 6.6 Store environment /work activities contributing to contaminant levels Finally, to examine other store environment or activity factors that may contribute to contaminant levels in the stores, we analysed the relationship between each of the three contaminants (dust, endotoxin, and viable fungi) and environment and activity factors listed in Table 11 below. Table 11: Store environment and work activity factors evaluated Factor Type Description outdoor temperature continuous degrees C (range: -8 to 25) indoor temperature continuous degrees C (range: 13 to 26.5) indoor relative humidity continuous % (range: 36 to 74%) water content of indoor air continuous lb water /lb air (range: 0.0046 to 0.0105) Ambient conditions median family income (in same postal code) continuous based on 1996 census data range: $27,450 to 63,113 days since floors were last washed continuous range: 0 to 13 Store cleanliness factors glass breaker steam cleaned in past month 2 categories yes / no or not known Store layout factors extent of crowding (visual inspection) 4 categories very crowded / crowded / somewhat crowded / wide open location of breaker relative to empties counter 3 categories Adjacent separated by a wall or partial wall separated by distance warehouse size (subjective assess.) 3 categories relatively small/ medium / large store located below grade 2 categories yes / no store located in enclosed mall 2 categories yes / no outdoor empties kiosk 2 categories yes / no number of glass bins filled on test day continuous range: 0.25 to 3.75 number of can bins filled on test day continuous range: 0.33 to 5 number of bin changes on test day continuous range: 0 to 2 beer bottle returns in prior month continuous range: 1849 to 31,304 dozen Empties recycling volume factors wine and spirits bottle returns in prior month continuous range: 3640 to 68,961 number of times bin raked on test day continuous range: 0 to 7 times number of times jams were cleared continuous range: 0 to 3 times spray cleaner used on breaker 2 categories yes / no glass bins covered 2 categories yes / no full bins in store, previous night 2 categories yes / no Activities associated with glass breaking visually contaminated bottles in glass breaking machine or broken manually 2 categories yes / no Machine factors type of glass breaking machine 4 categories glass aggregate rotary, single feed rotary, conveyor feed rotary conveyor, hydraulic use of local exhaust system 3 categories never or seldom used used when operating glass breaker always on Employee tasks % of employee time spent, test day: stocking shelves continuous range 0 to 100% working on loads / orders continuous range 0 to 100% working at the empties counter or operating the glass breaker continuous range 0 to 100% working at the cash station continuous range 0 to 100% working in an office, elsewhere in the front of the store continuous range 0 to 100% Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 42 of 76 6.6.1 Factors associated with inhalable particulate (dust): univariate (one-way) analyses: These analyses were done first by comparing each factor individually to each contaminant level (univariate analyses) and then using regression modeling to take all factors into account at the same time (multivariable analyses). For univariate analysis of continuous explanatory factors (e.g. temperature, volume of bottles returned in the previous month), we examined the correlation between the exposure variable (log scale) and the potential explanatory factor. For categorical explanatory factors, we compared the geometric mean exposure level for each category (with statistical testing based on analysis of variance). Only those factors that were significantly associated with any of the exposures are listed in the tables below. Table 12: Factors (continuous variables) associated with indoor personal dust exposure (log scale) – correlation coefficients correlation coefficient p1 store environment factors outdoor dust +0.26 <0.01 outdoor temperature - 0.12 <0.05 neighbourhood median income +0.26 <0.01 employee tasks, % of time spent: stocking shelves +0.14 <0.05 working on loads / orders +0.23 <0.01 p-value, correlation coefficient is significantly different from zero Table 13: Factors (categorical variables) associated with indoor personal dust exposure (log scale) – comparison of geometric mean values dust level, µg/m3 (geometric mean) p1 Store environment factors: crowded warehouse wide open or little crowding crowded or very crowded 0.190 0.164 0.05 Machine and recycling factors local exhaust system seldom / never used only when glass breaker is on always on 0.198 0.189 0.153 <0.05 glass bins covered no yes 0.190 0.176 <0.01 1 p-value from ANOVA, comparing (log) mean values Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 43 of 76 To summarize, indoor (personal) dust levels were positively correlated with outdoor dust, with neighbourhood income, with the proportion of time the employee spent stocking shelves and working on loads / orders; and negatively correlated with outdoor temperature. Average dust levels were also significantly lower in more crowded stores, in stores where the local exhaust ventilation system was kept on continuously, and where the glass bins were kept covered. 6.6.2 Factors associated with inhalable particulate (multivariable analyses): Because of the high degree of inter-relation among the various explanatory factors, univariate analyses can be too simplistic to fully explain the contribution of the work environment factors to exposure levels. Therefore, multiple linear regression models were analysed in which all explanatory factors were examined together (using a hierarchical approach to model building). This allowed us to examine which potential explanatory factors remained associated with exposure, after taking into account all possible explanatory factors together. Results are shown in the table below. The values in the first numeric column of the table are the regression coefficients from the 'best fit' model with inhalable particulate (log scale) as the dependent (or outcome) variable. The variables listed in the first column of the table are the variables that remained as significant predictor of exposure. In this type of analysis, the p-value indicates the significance level for the statistical test of whether or not the coefficient differs from zero. As the actual values of the coefficients vary depending on the range of the predictor variable, the coefficients themselves cannot be compared directly. Therefore, the final column of the table lists the relative contribution of each predictor variable to the model (% variability explained, or partial R2). These values are directly comparable. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 44 of 76 Table 14: Coefficients from the ‘best fit’ multiple linear regression model for inhalable particulate (ln transformed) coefficient p % variability in dust levels explained by the factor intercept 3.61 <0.001 environment: median income ($K) outdoor dust (log, mg/m3) 0.015 0.14 <0.001 <0.001 3.6 6.8 employee tasks (% of time) stocking shelves loads/orders in back empties/breaking 0.010 0.008 0.006 <0.001 <0.001 <0.05 3.1 5.0 1.4 machine related activities local exhaust always on -0.14 0.06 1.1 Model R2 adjusted R2 0.21 0.19 In this 'best fit' model, most of the same variables identified in the univariate analysis remained as significant predictors of increased dust levels (higher neighbourhood income, higher outdoor dust level, not using the local exhaust system all day, and employees spending more time stocking shelves and filling or unloading orders). In addition, the employees who spent more time working at the empties return counter or operating the glass breaker also had significantly higher exposure to dust. However, this model only accounted for about 20% of the variability in the overall dust levels, with outdoor dust being the largest single predictor, accounting 6.8% of the variability in indoor dust. This means that much of the variability in overall dust levels was not explained by any of the variables in the model. Time spent working on orders in the back of the store accounted for a further 5% of the variability, and time spent stocking shelves and working on the empties counter or operating the glass breaking machine only accounted for 3% and 1% respectively. None of the other store environment or machine related factors was linked to dust exposure levels in this study. When these explanatory factors were taken accounted for, the ‘regional’ and 'visit' differences described earlier disappeared (that is, these factors accounted for the lower exposure levels noted in the Victoria region and at visit 1). Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 45 of 76 6.6.3 Factors associated with endotoxin (univariate analyses): The identical process (univariate analysis followed by multivariable regression modeling) was followed to investigate factors that associated with endotoxin exposure levels The results are shown below. Table 15: Factors (continuous variables) associated with indoor personal endotoxin exposure (log scale) – correlation coefficients correlation coefficient p1 store environment factors indoor dust + 0.46 <0.001 indoor temperature - 0.18 <0.01 outdoor temperature - 0.25 <0.01 indoor absolute humidity - 0.22 <0.01 employee tasks, % of time spent: working at empties counter or operating glass breaker +0.17 <0.01 working on loads / orders +0.22 <0.01 p-value, correlation coefficient is significantly different from 0 Table 16: Factors (categorical variables) associated with indoor endotoxin exposure (log scale) – comparison of geometric mean values dust level, ng/m3 (geometric mean) p1 Machine and recycling activities local exhaust system seldom / never used only when glass breaker is on always on 0.57 0.34 0.35 <0.05 glass bins covered no yes 0.54 0.35 <0.01 breaking contaminated bottles no yes 0.44 0.34 0.05 glass breakers being used no yes 0.56 0.34 <0.01 Job title manager assistant manager clerk auxiliary clerk other 0.32 0.35 0.41 0.41 0.03 <0.01 1 comparing (log) mean values Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 46 of 76 Based on the univariate analysis, higher endotoxin levels were correlated with lower indoor and outdoor temperature and lower indoor absolute humidity. Average endotoxin levels were higher when no local exhaust was being used, when glass bins were covered, and when the glass breaking equipment was not being used. Clerks and auxiliary clerks had higher endotoxin exposure and endotoxin levels were positively associated with the amount of time employees spent at the empties counter or around the glass breaking machines and working on loads and orders in the back of the stores. As expected, personal endotoxin levels were highly correlated with personal dust exposure levels. 6.6.4 Factors associated with endotoxin (multivariable analyses): Multiple linear regression models were created for endotoxin, in which all explanatory factors were examined together, following the same approach as used for the dust analyses. Results are presented below in the same format. Table 17: Coefficients from the ‘best fit’ multiple linear regression model for endotoxin (ln transformed) ln endotoxin( ng/m3) p % variability in dust levels explained by the factor intercept -4.165 <0.001 environment: indoor dust (log, mg/m3) +0.83 <0.001 20.9% employee tasks (% of time) empties/breaking filling loads / orders +0.010 +0.008 <0.05 <0.05 1.4% 1.3% store is below grade (yes) +0.74 <0.01 2.4% absolute humidity (indoor) -176.4 <0.001 3.8% Model R2 adjusted R2 0.30 0.28 In this 'best fit' model, when all potential explanatory factors were taken into account together, only the following factors remained significantly associated with increased endotoxin exposure: increased indoor dust level, reduced absolute humidity indoors, the fact of the store being located below grade (which was associated with increased exposure in this model, although not significantly Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 47 of 76 associated with exposure in the univariate analysis), and the percentage of time employees spent working at the empties counter or running the glass breaker. The main contributor to personal endotoxin exposure was personal dust level (accounting for almost 21% of the variability in endotoxin). This finding is not unexpected given that the endotoxin was extracted from the dust samples. The other factors explained less than 10% of the variability in the overall exposure. Once dust level and the other factors listed in the table above were taken into account, neither job title nor ‘visit’ remained significantly associated with endotoxin exposures. This indicates, for example, that the apparent increased exposure among clerks and auxiliary clerks is due to the amount of time they spent working in the back of the store. 6.6.5 Factors associated with viable fungi (univariate analyses): Finally, to examine the additional store environment and activity factors that may be contributing to viable fungal exposures in the stores, we carried out analyses similar to those conducted for dust and endotoxin. Analyses were carried out for both average and peak fungal counts in the whole store (indoors) and in the warehouse and area surrounding the glass breaker. Only results from the analyses of store average exposures will be shown. The analyses based on peak exposures and analyses based on average exposures in the warehouse and average exposures in areas surrounding the glass breakers were similar and do not provide additional information. Employee specific factors (time spent in various tasks and job title) were not considered in these analyses, as fungal exposure was measured by stationary samples and are not directly referable to any one employee. Table 18: Factors (continuous variables) associated with indoor viable fungal levels (log scale) – correlation coefficients correlation coefficient p1 store environment factors indoor temperature + 0.26 <0.01 outdoor temperature + 0.43 <0.01 indoor absolute humidity + 0.22 <0.01 outdoor fungal counts + 0.22 <0.01 recycling volumes wine /spirits bottles returned, prior month + 0.17 <0.01 beer bottles (dozens) returned, prior month + 0.32 <0.01 number of glass bins filled on test day + 0.11 0.07 number of can bins filled on test day + 0.22 <0.01 p-value, correlation coefficient is significantly different from 0 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 48 of 76 Table 19: Factors (categorical variables) associated with indoor fungal exposure (log scale) – comparison of geometric mean values store environment factors: fungal counts CFU/m3 (geometric mean) p1 store below grade no yes 1033 2143 <0.05 warehouse size small medium large very large 633 1422 1064 2038 <0.01 outdoor empties kiosk no yes 1022 1790 <0.04 recycling activities breaking contaminated bottles no yes 639 1808 <0.001 glass breakers being used no yes 812 1200 <0.01 jams cleared on test day no yes 1043 1495 Glass breaking machine factors machine type glass aggregate rotary single feed rotary conveyor rotary conveyor, hydraulic 1002 862 1588 3790 <0.001 local exhaust system seldom / never used only when glass breaker is on always on 812 1236 1033 <0.05 machine steam cleaned, past mo. no yes 1118 898 0.10 1 comparing (log) mean values within the categories of the factor As can be seen from these tables, many more store environment factors were associated with fungal exposures than with dust or endotoxin. The univariate analyses show that average indoor fungal counts were positively correlated with indoor and outdoor temperature, indoor absolute humidity, and with outdoor fungal counts. They were also higher in stores handling a higher volume of empties (both beer and wine / spirits bottles). Significantly higher store average fungal counts were also found in stores below grade, those with larger warehouses, those with an outdoor empties return kiosk, in stores where glass breaking machines were operating, stores where jams were cleared in the glass breaking machine on the test day, and in stores where the local exhaust was used intermittently. Average fungal counts were also considerably higher if contaminated bottles were being broken in the store on the test day (over 2 Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 49 of 76 times higher than other stores and test days). The highest average fungal counts were seen in the one store with a hydraulic rotary conveyor machine and were also higher in stores with rotary glass breakers equipped with conveyor feed systems. The reason for this is not evident, but may be related to the increased volume of empty containers handled in these stores. The multiple regression model results in which all these factors (and others) were considered together is shown below. 6.6.6 Store environment factors related to viable fungal exposures: multivariable analyses Table 20: Coefficients from the ‘best fit’ multiple linear regression model for store average (indoor) fungal counts (ln transformed) coefficient p % variability in fungal counts explained by the factor intercept 7.03 <0.001 environment: outdoor temperature (0C) store below grade (yes) crowded warehouse + 0.76 + 0.68 - 0.50 <0.001 <0.001 <0.001 7.6 % 1.5 % 2.0 % volume / machine factors outdoor empties kiosk rotary conv. hydraulic rotary conveyor wine/spirits bottles returned, prior month machine steam cleaned, past month + 1.97 + 2.62 + 0.84 - 0.73 - 0.29 <0.001 <0.001 <0.001 <0.001 <0.05 4.2 % 2.4 % 6.6 % 2.6 % 1.0 % activities related to empties contam. bottles broken glass bins covered + 0.86 - 0.76 <0.001 0.05 20.0 % 5.2 % Model R2 adjusted R2 0.52 0.51 This 'best fit' model shows that, when all potential explanatory factors were taken into account at the same time, the single most important factor associated with increased store average fungal exposures was whether or not visually contaminated bottles were being broken in the store (either in the glass breaking machine – as was the case in most stores, or manually, as was being done in one store tested) on the test day. This factor explained 20% of the variability in fungal counts. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 50 of 76 The next most important explanatory factor was outdoor temperature. The most likely explanation for this was discussed above: the reduced ability of fungi to flourish in the drier indoor air resulting when cooler outdoor air is warmed for indoor use. Other important factors contributing to increased average fungal exposures were the presence of uncovered glass bins in the store and the use of rotary conveyor machines. Fungal exposures were slightly (and significantly) reduced in those stores in which the glass breaker had been recently steam cleaned. Once all these explanatory factors were taken into consideration in the analysis, there was no longer a significant difference between visit 1 and visit 2 fungal levels (i.e. ‘visit’ was not significant in the model). As discussed earlier, it is difficult to distinguish between the effect of machine type and that of the volume of empties being returned due to very high correlations among the various measures of return volume and the machine type. In the multivariable analysis, once machine type and the presence of an outdoor empties return kiosk were included in the model, it appeared that increased volume of returns was actually associated with reduced fungal counts. This paradoxical finding may be simply due to ‘over-correction’ by machine type, given the very high return volume in the one store with the hydraulic breaker. On the other hand, it may be that increased return volumes were associated with more rapid turnover of bottles in the stores and therefore, reduced fungal growth. Similar analyses were carried out to predict the average of fungal samples taken only in the ‘back’ of the stores (e.g. in the warehouse area and around the breakers and empties counter), and to predict only the samples taken around the glass breakers. The results were almost identical, with the same set of predictor variables significant; the only difference was that the model R2 (total amount of variability explained) was even higher (56%) in the model for fungal exposures in the back of the stores. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 51 of 76 7 Results: Characteristics of participants A total of 226 employees were included in the study, with only 44 being tested twice (i.e. at each of the 2 visits (table 21). Proportionately fewer auxiliary clerks were tested on the second visit, or tested twice. Table 21 : Jobs of participants, according to test occasion tested visit 1 only tested visit 2 only tested both visits total clerk 39 40 26 105 auxiliary clerk 47 28 9 81 assistant manager 9 7 9 25 manager 4 5 3 12 other 1 2 0 3 total 100 82 44 226 The small number of persons tested on both occasions was an unexpected finding as we had anticipated having access to a larger number of employees for repeat testing. Indeed, the original study design called for evaluation of the change in symptoms associated with change in exposures (comparing the two arms of the study). The small number of ‘repeat’ participants precluded such comparison. Therefore, analyses were confined to examining the relationship between symptoms and exposures in the study as a whole and in the two visits separately, taking into account store environment factors (including glass breaker operation) as well as specific exposure levels. 7.1 Demographic and health history characteristics of participants As respiratory and skin symptoms are typically associated with personal characteristics such as smoking, age, and history of other diseases, we evaluated the distribution of these factors in the study group (and in the comparison population). These results are shown in table 22 below. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 52 of 76 Table 22 - Demographic and general health characteristics of participants Total First tested visit 1 First tested visit 2 p (comparing v1 and v2) comparison group p LDB v. comp. Number tested Total 226 144 82 122 Age (years, average.) Total group 43.3 42.9 44.0 ns 47.1 <0.01 Smoking status Never Former Current 34% 35% 31% 37% 33% 30% 29% 39% 32% ns 35% 38% 27% ns Sex Female Male 52% 48% 45% 55% 54% 46% ns 33% 67% <0.01 Ethnicity Caucasian Other 91% 9% 91% 9% 91% 9% ns 86% 14% ns Average year employment with current employer in current job 13.5 7.6 13.6 7.5 13.4 7.8 ns ns 16.6 10.8 <0.01 <0.01 History of childhood asthma 7% 6% 8% ns 7% ns History of childhood hay fever 13% 15% 10% ns 7% 0.10 History of childhood eczema 10% 10% 10% ns 10% ns History of heart disease (requiring treatment) 5% 5% 5% ns 5% ns Karasek Job strain score* 0.84 (0.22) 0.86 0.83 ns 0.68 (0.14) <0.01 Work environment score** 6.0 (1.7) 6.1 5.9 ns * perceived psychological demands / task control (higher value = more 'job strain', range 0 - 2) ** work environment score: not assessed in comparison group (higher value='better' work envir., range, 1-10) There were no demographic or health history differences between the employees first tested at visit 1 compared to those first tested at visit 2. The comparison group was about 4 years older, on average, than the study group (with correspondingly more years of work tenure), and had proportionately more male employees (67% v. 48%). The two groups were similar with respect to smoking status, ethnicity, history of relevant Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 53 of 76 diseases diagnosed before the age of 16 (asthma, eczema, hay fever), and history of heart disease. These prior health similarities are useful indicators of the suitability of the BC Ferries employees in providing comparison data for ‘expected’ rates of symptoms. 7.2 Psycho-social aspects of work Two indicators of psychosocial aspects of work were included in this study. Job strain (a construct based on previous research by Karasek)(8) is the ratio of perceived psychological demands of the work to the level of control over job tasks. The work environment score is a composite measure of job satisfaction and the employees’ assessment of employer/employee communication and co- operation. Job strain has been shown to be correlated with adverse health outcomes in other studies, presumably through increased stress in ‘high strain’ jobs.(12) Compared to BC Ferry employees, LDB employees rated their work as having a significantly higher level of job strain and a lower work environment score. Job strain and workplace environment scores were further examined among the LDB study group, according to job title and region. Auxiliary clerks reported the highest job strain and lowest workplace environment scores, and managers and employees with 'other' job titles the reverse (p=0.05, for job strain; p<0.01 for workplace environment score). There was no significant difference in job strain scores by region, but there were significant regional differences in the average workplace environment scores (with stores in the Vancouver ‘west’ region having significantly lower scores, on average, than stores in other regions, p<0.01). Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 54 of 76 7.3 Chronic symptom prevalence rates The health assessment was limited to evaluating those chronic and acute symptoms frequently associated with exposure to aerosolized irritants and bio-aerosols. Chronic symptom assessment was based on responses to a standardized questionnaire, identical to that used by our research team in studies at other BC workplaces. Prevalence rates for these symptoms are shown below. Table 23: Chronic symptoms: LDB employees compared to BC Ferry Corporation employees Chronic Symptoms LDB First tested visit 1 First tested visit 2 p1 Comparison Group p2 Odds Ratio3 number 226 144 82 122 Cough usual cough work-related cough 14% 5% 11% 6% 18% 5% ns ns 11% 7% ns ns ns ns Phlegm usual phlegm work-related phlegm 10% 2% 9% 1% 11% 2% ns ns 22% 5% <0.01 ns 0.4 (0.2,0.8) ns Wheeze occasionally, apart from colds wheezing with breathlessness work-related wheeze 21% 12% 11% 18% 8% 7% 26% 20% 18% ns <0.05 <0.01 21% 11% 8% ns ns ns ns ns ns Chest tightness episodes or attacks work-related chest tightness 31% 8% 24% 4% 41% 15% <0.01 <0.01 17% 2% <0.01 <0.05 1.9 (1.1, 3.4) 4.8 (1.1, 21.7) Shortness of breath hurrying on the level walking on the level 17% 4% 16% 3% 17% 5% ns ns 22% 7% ns ns ns ns Nasal symptoms sneezing, itching, running work-related nasal symptoms 61% 31% 60% 28% 63% 35% ns ns 49% 13% <0.05 <0.01 1.4 (0.9,1.8) 2.9 (1.5, 5.4) Eye symptoms burning, itching, watering work-related eye symptoms 15% 8% 17% 7% 13% 9% ns ns 19% 3% ns 0.10 ns 2.5 (0.8, 8.0) Asthma, current, physician diagnosed diagnosed in past 3 years 8% 1% 6% 1% 16% 2% <0.05 ns 10% 3% ns ns ns ns Hay fever, current, physician diagnosed diagnosed in past 3 years 19% 2% 19% 2% 17% 2% ns ns 12% 0 ns ns ns ns Eczema, current, physician diagnosed diagnosed in past 3 years 16% 2% 17% 3% 20% 2% ns ns 12% 2% ns ns ns ns 1 comparing LDB employees first tested at visit 1 to those first tested at visit 2 2. comparing LDB employees to BC Ferry employees 3. Odds Ratios, logistic regression models, taking differences in age and gender into account Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 55 of 76 Within the LDB study population, significantly more current asthmatics were included in the group tested at visit 2 than at visit 1, although this difference was not seen among asthmatics diagnosed only recently. The rate of current asthma among LDB employees (8%) was not significantly different from the rate in the comparison group (10%). There was a higher prevalence of wheezing and chest tightness among participants first tested during the second visit. This is in direct proportion to the higher number of asthmatics tested during visit 2. Taking this into account, the comparison above suggests that there was no unexplained differential in the rate of chronic symptom reporting over the time span of the study. Comparison of chronic symptom prevalence rates of LDB employees to ‘expected’ rates based on the comparison group reveals that LDB employees had significantly higher rates of chronic chest tightness (both in general and related to work), nasal symptoms (in general and related to work) and work-related eye symptoms. The increased risks (after taking into account differences in gender and age between the two groups) were over 2 times for work-related nasal and eye irritation symptoms and over 4 times for work-related chest tightness Rates for other symptoms were similar to those of the control group, except for chronic phlegm production which was reported less frequently among LDB employees. To some extent, the lower reported rate of chronic phlegm production in LDB workers may be due to the relatively larger percentage of females in this group compared with BC Ferry workers. 7.4 Acute symptoms 7.4.1 Prevalence rates by visit, study group Acute symptoms were assessed by asking each employee to report the occurrence, frequency and severity, in the previous week, of specified symptoms. For this analysis, an acute symptom was only deemed present if it was reported to have occurred more than once in the previous week and with greater than minimal severity. In contrast to chronic symptoms (which are expected to reflect the impact of exposures over an extended period of time), it is expected that acute symptoms are a better reflection of recent changes in the environment. Prevalence rates for each of the acute symptom assessed are shown below, stratified according to visit and study arm. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 56 of 76 Table 24: Acute symptom prevalence, by visit, group visit 1 visit 1 visit 2 visit 2 p1 p2 Regular Operations, no shutdown Regular Operations but will shutdown Regular Operations Breaker not in operation n 79 66 67 59 dry cough 26.6 % 24.2 % 41.8 %* 33.9 % ns <0.05 cough with phlegm 24.1 % 15.2 % 26.9 % 16.9 % ns ns wheeze 6.3 % 4.5 % 16.4 %* 8.5 % ns <0.05 chest tightness 12.7 % 10.6 % 14.9 % 6.8 % ns ns breathlessness 10.1 % 9.1 % 19.4 % 3.4 % <0.01 ns irritated nose 29.1 % 31.8 % 38.8 % 39.0 % ns ns runny/stuffy nose 44.3 % 37.9 % 59.7 %* 54.2 %+ ns <0.05 irritated throat 29.1 % 22.7 % 35.8 % 15.3 % <0.01 ns sinus trouble 13.9 % 13.6 % 22.4 % 22.0 % ns 0.07 irritated eyes 21.5 % 30.3 % 25.4 % 23.7 % ns ns vision disturbances 8.9 % 9.1 % 7.5 % 10.2 % ns ns taste disturbances 3.8 % 4.5 % 10.4 % 3.4 % ns ns voice disturbances 16.5 % 7.6 % 14.9 % 6.8 % ns ns fever 3.8 % 1.5 % 4.5 % 3.4 % ns ns headache 13.9 % 24.2 % 26.9 %* 20.3 % ns ns dizziness 2.5 % 3.0 % 4.5 % 6.8 % ns ns tiredness 24.1 % 16.7 % 23.9 % 20.3 % ns ns joint pains 38.0 % 30.3 % 29.9 % 32.2 % ns ns skin irritation 11.5 % 4.6 % 19.4 % 8.5 % 0.08 <0.05 bleeding from nose 6.3 % 1.5 % 10.4 % 5.1 % ns ns other unusual bleeding 1.3 % 0 0 1.7 % ns ns infections 1.3 % 0 3.0 % 3.4 % ns ns URT infection 0 0 10.4 %* 10.2 %* ns <0.01 other symptoms 3.8 % 1.5 % 4.5 % 6.8 % ns ns 1. comparing 'regular operations' to 'breaker shut-down', visit 2 only; 2. comparison between visits: ie. comparing all visit 2 (both groups combined) to all visit 1 (both groups combined) + p < 0.10; * p <0.05, comparing visit 2 to visit 1 results, within the study arm Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 57 of 76 There were no significant differences in symptom reporting between the two groups of stores during visit 1 (no ‘p-values’ shown in the table as they were all > 0.2 or ‘not significant’). Comparing visit 2 (overall) to visit 1, symptom reporting was increased for several symptoms (p - values shown in the last column of the table), including dry cough, wheezing, runny / stuffy nose, sinus complaints, skin irritation, and recent 'cold or flu'. It is likely that at least some of this increase in symptoms was linked to increased viral infections during the winter months. Comparing acute symptom reporting between the stores in the 2 arms of the study, within visit 2, (p-values shown in the second last column of the table), it is evident that the increased symptom reporting was, in some cases, not equal across the study arms. Increased recent cough and wheezing was only elevated in stores where the glass breakers continued to operate; increased nasal symptoms was reported in stores in both arms of the study. 7.4.2 Acute symptom complexes When information is gathered about a large number of symptoms (such as in this study), it is customary to group these in some fashion, in order to reduce the likelihood of seeing 'spurious' associations by chance alone. For all subsequent analyses, several of these acute symptoms were grouped as follows: • nose or throat irritation: 2 or more of the following symptoms, more than once in the past week: irritated nose, throat, voice, or taste disturbances • chest symptoms: 2 or more of the following symptoms, more than once in the past week: cough, wheezing, chest tightness, breathlessness • somatic symptoms: 2 or more of the following symptoms, more than once in the past week: fever, headache, dizziness, tiredness, nausea In addition, subsequent analyses also included the following individual symptoms: irritated eyes, irritated skin, nosebleeds, and unusual infections as these have been the subject of employee complaints. Prevalence rates for the grouped symptoms (by visit and study group) are shown below: Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 58 of 76 Table 25: Acute symptom complexes, by visit and group Visit 1 Visit 2 regular operations regular operations, but breaker to be shut, V2 p1 regular operations breaker shut down p1 p2 Nose/throat irritation 22% 18% ns 25% 15% ns ns Chest symptoms 14% 11% ns 27%* 10% <0.05 <0.05 Somatic symptoms 6% 9% ns 19%* 10% ns 0.05 1. comparing 'regular operations' to 'breaker shut-down' 2. comparing visit 2 (both groups combined) to visit 1 (both groups combined) * P<0.05, comparing visit 2 to visit 1 results, within the study arm These results present a similar picture to the individual symptoms. Both chest and somatic symptoms were elevated in visit 2 over visit 1, and this increase was confined to employees in the stores where the glass breakers continued operations. 7.4.3. Personal factors associated with acute symptom reporting Preliminary analyses were carried out to examine the relationship between symptom reporting and potential explanatory factors other than workplace exposures, including cigarette smoking, age, gender, history of childhood diseases, job title, and region. None of the symptoms was associated with age or gender (results not shown). History of childhood asthma was associated with a significantly increased risk of nosebleeds (16%, compared to 5%, p<0.05). Skin irritation was more prevalent among persons who had a childhood history of eczema (33% compared to 11%, p < 0.01). Current smokers had significantly higher reporting of skin irritation than former smokers or current non-smokers (see table 26 below). None of the other acute symptoms or symptom complexes showed any association with smoking status. Only eye irritation showed a significant difference as a function of job title with clerks reporting the highest levels and managers/others the lowest (table 27). Regional differences were seen for nose/throat irritation, eye irritation, and skin irritation with high prevalence rates for each of these symptoms in stores in the west of Vancouver and high prevalence of nose / throat irritation in east side Vancouver stores as well (table 28). However, no one region had consistently higher or lower symptom rates across all symptoms. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 59 of 76 Table 26: Acute symptoms and symptom complexes by smoking status total non-smokers former smokers current smokers N 270 87 99 84 p Nose / throat irritation 20% 23% 19% 19% ns Chest symptoms 16% 14% 15% 18% ns Eye irritation 15% 28% 23% 24% ns Somatic symptoms 11% 13% 10% 11% ns Skin irritation 11% 9% 7% 18% 0.05 Nose bleeds 6% 5% 6% 7% ns Infections 2% 2% 3% 0 ns Table 27: Acute symptoms and symptom complexes by job clerks auxiliary clerks assistant managers managers / others p N 131 87 34 13 Nose / throat irritation 19% 25% 21% 5% ns Chest symptoms 14% 21% 15% 0 ns Eye irritation 31% 24% 15% 0 <0.05 Somatic symptoms 11% 13% 9% 6% ns Skin irritation 14% 8% 12% 6% ns Nose bleeds 5% 7% 6% 6% ns Infections 2% 1% 0% 6% ns Table 28: Acute symptoms and symptom complexes by region Fraser Valley Van East Van South Van West Mid Island Victoria BC interior p N 34 48 37 29 35 51 36 Nose / throat irritation 24% 35% 16% 31% 6% 8% 25% <0.01 Chest symptoms 15% 19% 5% 28% 14% 18% 11% ns Eye irritation 32% 19% 19% 48% 14% 29% 17% <0.05 Somatic symptoms 9% 15% 5% 17% 14% 12% 6% ns Skin irritation 15% 12% 5% 24% 0 12% 11% 0.08 Nose bleeds 6% 10% 0 7% 3% 8% 6% ns Infections 0 6% 0 0 3% 0 0 ns Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 60 of 76 8 Results: Relationships between contaminant levels and symptoms In addition to assessing the potential relationship between the operation of glass breaking equipment and symptom reporting, we investigated the relationship between symptom reporting and measured levels of environmental contaminants, recycling activities, and other store environment variables independent of whether or not the glass breakers were operating. Results are shown first for acute symptoms and then for chronic symptoms. As described above for the analyses of store environment factors associated with personal and area monitoring, univariate analyses were performed first, followed by multivariate analyses to consider all possible explanatory factors together. 8.1 Acute symptoms 8.1.1 Univariate analyses: symptoms related to dust / endotoxin exposure The occurrence of acute symptoms and symptom complexes in relation to measured dust and endotoxin exposure (categorized as discussed earlier) are shown in table 29 below. Table 29: Acute symptom complexes: relationship to dust /endotoxin exposure levels Dust Endotoxin < 200 ug/m3 > 200 ug/m3 p < 1 ng/m3 > 1 ng/m3 p 156 114 215 55 Nose / throat irritation 15% 27% 0.01 19% 27% 0.1 Chest symptoms 14% 18% ns 15% 16% ns Eye irritation 25% 25% ns 24% 29% ns Somatic symptoms 11% 11% ns 11% 11% ns Skin irritation 12% 11% ns 13% 11% ns Nose bleeds 6% 6% ns 6% 7% ns Infections 3% 1% ns 2% 0 ns Nose / throat irritation was significantly associated with higher inhalable particulate exposure, with approximately twice the rate of symptom reporting among employees whose dust exposure was in the higher range (> 0.200 mg/m3). None of the other symptoms or symptom complexes were associated with the measured exposure to dust or endotoxin in the univariate analyses. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 61 of 76 8.1.2 Univariate analyses: fungal levels Parallel analyses for exposure-response relationships between fungal levels and symptoms were hindered by the very strong seasonal difference in fungal levels from visit 1 to visit 2. Therefore, analysis of the relationship between fungal levels and symptoms was carried out for each test visit separately. Similar analyses were carried out using different cut points for peak and average fungal level; results did not differ appreciably from those shown here. Table 30: Acute symptoms: relationship to peak fungal levels Visit 1 Visit 2 < 3000 CFU > 3000 CFU p < 3000 CFU > 3000 CFU p 77 67 83 43 Upper airway irritation 22% 18% ns 22% 19% ns Chest symptoms 18% 8% 0.07 19% 19% ns Eye irritation 25% 25% ns 23% 28% ns Somatic symptoms 7% 8% ns 16% 14% ns Skin irritation 10% 10% ns 16% 16% ns Nose bleeds 4% 4% ns 7% 9% ns Infections 1% 0 ns 4% 2% No significant associations were seen between the fungal levels measured in this study and symptom reporting. One of the limitations of the fungal sampling method used commonly in workplace and environmental studies (and used here) is that it only captures brief ‘point-source’ concentrations. In an environment where sources may vary considerably over time and space (such as in this study), such short term, brief area samples may not be an unbiased measure of the ‘average’ exposure over time. Therefore, we reviewed the results of the analyses to investigate predictive factors for fungal level and tested the explanatory variables from those models in analyses relating them to symptom reporting. These factors included outdoor temperature, the store being below grade, having a crowded warehouse, machine type, the volume of empties returned in the previous month, recent steam cleaning of the glass breaking machine, having uncovered glass bins, and contaminated Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 62 of 76 bottles being broken in the store on the test day. The only factor associated with increased reporting of acute symptoms was contaminated bottles being broken in the store on the test day (Table 31). Table 31: Acute symptoms and symptom complexes, according to whether or not visually contaminated bottles were being broken in the store on the test day (by visit) visit 1 visit 2 no yes p no yes p N 44 97 91 35 Nose / throat irritation 18% 21% ns 19% 26% ns Chest symptoms 5% 16% <0.05 16% 26% 0.2 Eye irritation 25% 25% ns 22% 31% ns Somatic symptoms 7% 7% ns 12% 23% 0.1 Skin irritation 9% 10% ns 12% 26% 0.06 Nose bleeds 0 6% 0.09 8% 9% ns Infections 0 1% ns 3% 3% ns Increased frequent chest symptoms were reported consistently by employees in stores where visually contaminated bottles were being broken (p< 0.05 at visit 1, with a similar trend at visit 2). This suggests a link between fungal levels, which are clearly associated with breaking contaminated bottles, and chest symptoms, although the evidence is indirect. 8.2 Exposure-response relationships (multivariate analyses): In order to take into consideration all potential explanatory factors for symptoms reporting together, multiple logistic regression modeling was carried out following the same approach as described earlier for analysis of workplace factors relating to exposure levels. For these analyses, potential explanatory variables were grouped as follows: • exposure variables : dust, endotoxin, mean CFU (in back of store), max CFU (in back of store) - variables were offered as continuous variables and as categorical variables • age, gender, smoking (status and amount), history of childhood asthma, hay fever, and eczema • use of protective equipment (mask, gloves, eyewear) • workplace environment and job strain scores Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 63 of 76 • job title • ambient environment factors: temperature, humidity etc. • store characteristics: machine type, volume of empties handed, ventilation, breaking contaminated bottles, and other factors as described earlier • glass breaker operation in the past month Logistic regression models were constructed for each acute symptom outcome separately, considering the effect of each of the factors listed above (results not shown). In all of these models, the only factors significantly associated with any of the acute symptoms or symptom complexes (after taking all factors into account together) were: dust exposure levels, breaking contaminated bottles, job strain score, work environment score, smoking status, and history of childhood diseases. In order to allow direct comparison the effects of these factors on the different symptoms and symptom complexes, subsequent analyses were performed including all these remaining variables in each model, plus endotoxin and fungal levels (in order to evaluate all exposures together) and an indicator variable to demonstrate the effect of operating the glass breakers in the prior month. Results from these final multivariable logistic regression models are shown in Table 32 below. The table shows values for \"odds ratios\" from multiple logistic regression models for each of the symptoms or symptom complexes shown at the head of each column. The odds ratio is an estimate of the increased risk for having the symptom, associated with each of the factors listed in the rows. If the risk is increased, the 'odds ratio' will be larger than one. For example an odds ratio of 2 means that the risk is about twice as high where the factor (listed in the row) was present, compared to where it was absent. The numbers in brackets following the odds ratio is the 95% confidence interval. If the lower 95% confidence limit is above 1, the odds ratio is statistically elevated (p<0.05). Odds ratios in bold in the tables are significantly high (or low). Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 64 of 76 Table 32: Odds ratios from multivariable models for acute symptoms and symptom complexes Nose / throat irritation Chest symptoms Somatic symptoms Eye irritation Skin irritation Nosebleeds number with symptom 54 42 29 67 29 16 dust > 200 ug/m3 (yes/no) 2.3 (1.1, 4.3) 1.5 (0.7,3.2) 0.9 (0.4, 2.1) 0.8 (0.4,1.5) 0.9 (0.4, 2.2) 1.1 (0.3, 3.5) endotoxin > 1 ng/m3 (yes/no) 1.5 (0.7,3.2) 1.0 (0.4,2.6) 0.8 (0.3, 2.4) 1.4 (0.7,2.9) 0.8 (0.3,2.5) 1.2 (0.3,5.0) average indoor fungal count > 3000 CFU (yes/no) 0.5 (0.2,1.1) 0.3 (0.1, 0.7) 0.6 (0.2, 1.5) 0.9 (0.5,1.8) 0.4 (0.2,2.2) 0.6 (0.2, 2.3) contaminated bottles broken (yes/no) 1.6 (0.7, 3.5) 2.6 (1.1, 6.4) 1.1 (0.4, 3.1) 1.4 (0.6, 3.1) 1.4 (0.5, 4.1) 2.3 (0.5,10.1) glass breaker operating, past month (yes/no) 1.6 (0.6, 4.0) 1.7 (0.6, 4.9) 1.2 (0.5, 3.9) 0.8 (0.3, 1.7) 1.1 (0.4, 2.5) 0.7 (0.2 3.2) high job strain score (yes/no) 1.2 (0.6,2.6) 0.8 (0.3,1.8) 2.4 (1.0, 5.7) 2.8 (1.4, 5.3) 3.9 (1.6,9.6) 0 low workplace environment score (yes/no) 1.4 (0.7, 2.9) 2.6 (1.2, 5.6) 2.1 (0.9, 5.1) 1.8 (0.9, 3.4) 1.5 (0.6, 3.9) 3.5 (1.1, 11.0) Current smoker (yes/no) 0.8 (0.4, 1.5) 1.2 (0.6, 2.6) 0.8 (0.3, 2.1) 1.0 (0.5, 1.8) 2.9 (1.0, 8.3) 1.3 (0.4, 3.8) childhood asthma (yes/no) 2.0 (0.7, 5.9) 2.1 (0.7, 6.6) 0.5 (0.1, 4.2) 1.4 (0.5, 4.2) n/a 3.4 (0.8, 14.3) childhood eczema (yes/no) n/a n/a n/a n/a 2.8 (1.2 6.7) n/a These results did not differ appreciably when an additional variable was added to account for auxiliary clerks who did not work at the same store the previous day, nor did they differ if the variable to identify high fungal exposure was removed from the models. The same analyses were repeated including a variable to take into account recent upper respiratory tract infection (associated with increased reporting of nose and throat irritation, chest symptoms, and somatic symptoms). Its inclusion in the models did not change any of the other odds ratios. The analyses were also repeated using actual values for personal dust and endotoxin (log transformed) rather than categorical ones and again using store average values in place of individual values. Similar results were found as shown above. Substituting peak fungal levels for average values did not change the results. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 65 of 76 Redoing the analyses to take into account the non-independence associated with the 44 repeated measures (from employees tested twice) did not change any of the conclusions. In summary, the results from multivariate models to examine work related risk factors for acute symptoms indicate that nose and throat irritation and chest symptoms (dry cough, wheezing, chest tightness, and breathlessness) were significantly associated with exposures in the work environment: nose and throat irritation with increased dust levels and chest symptoms indirectly linked to the increased exposures associated with contaminated bottles being broken in the store. These results were consistent with similar findings based on the univariate analyses. There were significant increases in eye and skin irritation, in somatic symptoms, and nose-bleeds among LDB employees that were strongly linked to psychosocial aspects of the work including high job strain (increased demand/control ratio) and lower work environment scores (reflecting less effective employee / employer communication and co-operation at work). Increased chest symptoms were also linked to these factors. As this study was not designed to address these in any detail, no further comment can be made regarding these findings. 8.3 Cross-sectional analysis of chronic symptoms (visit 1 results) The study was not designed specifically to address exposure-response relationships between chronic symptoms and exposures, as no past measures or estimates of exposures were available. However, limited investigation of exposure risk factors for chronic symptoms was attempted. We restricted this analysis to regular employees tested at visit 1 only, since only the visit 1 results reflect an ‘unbiased’ cross-sectional look at the population, with no advance notice and no intervention. Auxiliary employees were also excluded, reasoning that the store average exposure data would not be directly relevant. A total of 91 employees remained for these analyses. In order to estimate the 'typical' workplace exposure levels for dust, endotoxin, and fungi for employees in a given store (rather than the individual value measured on one day only), for this analysis we used the average of the values for all employees in each store. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 66 of 76 As in the analyses including all participants (described earlier in this report), chronic chest tightness and nasal symptoms (worse at work) were increased in this subgroup when compared to BC Ferry Corporation employees. None of the chronic symptoms was significantly associated with the store average measures of dust, endotoxin, nor viable fungi, nor to specific work environment factors or tasks. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 67 of 76 9 Summary and Discussion The objective of this project was to compare exposures associated with glass recycling and symptoms to determine if there was a relationship between contaminants linked to glass breaking / recycling and acute or chronic symptoms, and to evaluate other possible risk factors for symptoms among LDB employees. We conducted the study at 36 BC liquor stores, selected at random. Theses stores were similar in size, volume of business, and type of glass breaking machine to other BC liquor stores, indicating that the results can be generalized beyond the stores included in the study. Each store was tested twice, approximately 1 month apart. In half the stores (selected at random), the glass breaking equipment was shut down between visit 1 and visit 2. 9.1 Exposures Dust (inhalable particulate) was measured over the full work shift, for each employee. The average level found was 0.21 mg/m3 (median: 0.18 mg/m3) and dust concentrations ranged from less than detectable to 1.84 mg/m3. These concentrations were about 4 times higher than those found outdoors at the loading bay (median 0.05 mg/m3) but lower than WBC regulatory exposure limits for amorphous silica (4 mg/m3) and for particulate 'not otherwise classified' (10 mg/m3). The dust levels were similar to those seen for office-based employees in the lumber and grain industries and for lumber mill workers who work in the log receiving end of the sawmill. The dust levels were about 10 times lower than those seen among employees working in visibly dusty areas of sawmills and grain elevators. The only factors associated with increased employee dust exposures were increased outdoor dust levels (in the loading bay area) and employee work tasks. The more time an employee spent stocking shelves, filling loads or unloading, and working at the empties counter / glass breaker, the higher his or her dust exposure. Operating the local exhaust system all day contributed to a slight reduction in dust levels. However taken together, all these factors (outdoor dust, employee tasks, Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 68 of 76 and local exhaust) accounted for less than 20% of the variability in dust levels. This result suggests that the dust measured may be combination of outdoor dust being brought indoors, dust from shelf stocking operations, and dust from the glass breaking operations. However, no chemical analyses were carried out to examine the specific makeup of the dust collected. Endotoxin was extracted from the personal dust samples. Average levels for endotoxin were 0.75 ng/m3 (median: 0.37 ng/m3) and ranged from less than detectable to 10.5 ng/m3. These levels were about 10 times higher than outdoor samples (median 0.03 ng/m3), but lower than a recently proposed Dutch health-based exposure limit of 20 ng/m3. They were also lower, by up to 1000 times, than endotoxin levels seen in dusty areas of BC grain elevators (although similar to levels found in office areas in grain elevators). Indoor endotoxin levels were highly correlated with indoor dust levels. Endotoxin levels increased the more time an employee spent in the warehouse area of the store. However, as with dust exposure, we were only able to explain a small fraction of the variability in endotoxin levels with the factors recorded in this study. Viable fungal exposures were measured from several 5-minute area samples taken in locations throughout the stores. Counts ranged from not detectable to over 18,000 CFU/m3 (the upper limit given the method used here), with an overall average of 1791 CFU/m3 (median 500 CFU/m3). This average value is above the Health Canada guideline at which investigation of office buildings for indoor fungal sources is recommended (500 CFU/m3 ).(11) Average exposures near the cash desk were also somewhat higher than this guideline. There was a clear seasonal decline in fungal exposure over the study months, with average exposures markedly lower during the second visit testing. When the seasonal trend was taken into account (by including outdoor temperature in the analyses) the ‘visit’ effect was no longer significant. Fungal counts were clearly associated with glass recycling activities (highest around broken bottles, next highest elsewhere in the warehouse, lowest at the cashier station). Average viable fungal counts in the warehouse area of the stores, near the empties counters, and near the glass breaking equipment and bins were 3 – 8 times higher than outdoor average values. The most important single factor associated with increased store average viable fungal counts was whether or not visually contaminated bottles were being broken in the store (either mechanically or Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 69 of 76 manually) on the test day. This factor alone accounted for 20% of the variation in fungal counts. Fungal levels were also higher in stores with rotary conveyor and rotary hydraulic glass breaking machines and stores with outdoor empties return kiosks. This increase may be related to the increased volume of returns handled by these stores. Although there was clear evidence that fungal exposures were higher in proximity to glass breaking equipment, fungal exposures were not obviously lower when the glass breaking equipment was not operating. It would appear therefore, that glass recycling as a whole is contributing to fungal exposures, not simply operating the glass breaking machines. Clearly, receiving and breaking contaminated bottles was an important contributing factor. Another possible contributing factor that could not be examined fully in this study, is that some machines may have become contaminated with fungi and thus may represent a persistent exposure source. We did detect a slight drop in viable fungal counts on average associated with recent steam cleaning of the machines. 9.2 Employee symptoms Overall, LDB employees reported more chronic chest tightness (31% v. 17%) and nasal symptoms (61% v. 49%) than ‘expected’ based on comparison with a control group. For ‘work-related’ symptoms, the relative risk for LDB employees was even greater compared to ‘expected’ (4.8 times higher for chest tightness, 2.9 times higher for nasal symptoms, and 2.5 times higher for eye irritation). In similar occupational studies, one often sees lower rates of symptoms than ‘expected’ due to a ‘healthy worker effect’.(13) This ‘effect’ refers to the tendency of symptomatic employees (in all industries) to move away from jobs that they perceive as causing an adverse impact on their health. In this population, it is unlikely that such a ‘healthy worker effect’ has had the opportunity to contribute as the glass recycling is a relatively new procedure and because there is limited opportunity to move to a ‘low exposed’ job. In total when asked about acute symptoms occurring more than once in the past week, 20% of LDB employees reported 2 or more symptoms relating to nose or throat irritation (including voice Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 70 of 76 or taste disturbances), 16% reported two or more chest symptoms (cough, wheeze, chest tightness, breathlessness), 25% reported eye irritation, 11% reported skin irritation, 11% reported 2 or more constitutional symptoms (headache, tiredness, nausea, dizziness, fever) and 6% reported nosebleeds. Of particular interest in this study is whether the pattern of acute symptom reporting differed in stores in the two arms of the study. In the stores where the glass breaking equipment continued to operate, there was a significant increase in prevalence rates for dry cough, wheezing, and nasal symptoms experienced in the past week from visit 1 to visit 2. No increase was seen for dry cough or wheeze in the stores where the glass breaking equipment was shut down between visit 1 and visit 2. The increase in acute symptoms in stores in the ‘regular operations’ arm may have been seasonal, as visit 2 testing was conducted during the ‘cold and flu’ season. The lack of change in acute symptom prevalence rates in the stores in the ‘machine shut-down’ arm may have been due to a relative decrease in symptoms associated with lower work exposures being offset by a seasonal increase. It is also possible that the increase in symptoms in the one study arm only may have been linked in some way to increased employee awareness or concern about continued glass breaking activities, especially in face of the well publicized proposed moratorium on glass breaking that was reported in January 2001. One limitation of this study that must be kept in mind is that the intervention (i.e. shutting down the glass breaking equipment for one month in half the stores) was not ‘blind’. Therefore, the possibility for some bias in the visit 2 testing is inevitable. It is also possible that both factors described above could have contributed to the differential reporting of acute symptoms in the two study arms. 9.3 Relationship between work exposures and symptoms As summarized above, on average, symptom reporting increased in direct relationship to continued operation of the glass breaking machines. However, this continued operation of glass breaking Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 71 of 76 machines was not associated with higher exposures levels, on average, for any of the contaminants measured. This does not mean that symptoms were not linked to exposures necessarily, but rather that it is necessary to look more closely at the analysis of exposure-response relationships that take into account all factors together (i.e. the multivariable analyses described in section 8.2). The exposure-response results showed that increased inhalable particulate exposure was associated with a 2-fold increase in nasal and throat irritation among LDB employees (p<0.05). The only other factor linked to a similar rate of increase in nasal and throat irritation was a history of childhood asthma (but this was not statistically significant at p<0.05 level). The association between dust exposure and this symptom complex was not modified by whether the glass breaking machines were operating or not. Increased chest symptoms were not associated with any of the measured exposures. However, chest symptoms were increased (over 2½ times) in association with the most important ‘surrogate’ measure of fungal contamination, namely, stores where visually contaminated bottles were being broken on the test day (p<0.01). This relationship held regardless of whether the glass breaking machines were operating or not. The most likely explanation for the fact that chest symptoms were associated with a ‘surrogate’ marker for fungal exposure (moldy bottles being broken in the store) but not with measured fungal exposures is that the measurement technique used is likely only a blunt indicator of the biologically relevant exposure associated with fungal contamination in these stores. It has been clearly demonstrated in other studies that both viable and non-viable fungal spores and their constituents and products can be linked to respiratory and other irritant symptoms.(5;14;15) The measure used here captured only viable spores. Further, in an environment such as this where the occurrence of the exposure source (in this case, moldy bottles) can vary considerably over days and weeks, taking a relatively small number of samples on 2 test days may not reflect accurately the overall averaged burden of exposure. Given this limitation, the results suggest that fungal exposure associated with recycling mould contaminated bottles was linked to increased reporting of acute chest symptoms among LDB employees. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 72 of 76 Similarly, there was a suggestion that frequent nosebleeds among LDB employees may also be linked to this same surrogate marker of mould exposure. However, this trend was not statistically significant. There did not appear to be any association between endotoxin levels and acute symptoms in this study. This is likely because the endotoxin exposures were well below levels that can provoke symptoms. Finally, when we examined exposure – response relationships for chronic symptoms, we found no evidence of an association between the measured exposure levels or surrogate exposure markers and any of the chronic symptoms recorded. This finding suggests that the impact of glass recycling is either acute only or that it has not had sufficient time to make an impact on chronic symptoms. It is not possible to distinguish between these two possibilities from the results of this study. 9.4 Psychosocial aspects of work: impact on symptoms As described in the methods section, one part of the UBC chronic symptoms questionnaire contains a standardized series of 10 questions from which a ‘job strain’ score can be calculated and 4 questions contributing to a ‘work environment’ score. The job strain score measures an individual’s assessment of the ‘demand/control balance’ in his or her work (or the perceived psychological demands of work compared to the extent of individual control over work tasks). The work environment score assesses combination of job satisfaction and employee-employer communication. Compared to BC Ferry employees, LDB employees rated their work as having a significantly higher level of job strain (p<0.05). When job strain and the work environment score were considered in relation to the prevalence of acute symptoms, high job strain was linked to increased reporting of somatic symptoms (2 fold), eye irritation (almost 3 fold), and skin irritation (almost 4 fold). A low work environment score was also associated with increased chest symptoms (2 fold) and nosebleeds (3 fold). Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 73 of 76 Taking these psychosocial factors into account did not reduce the association between nasal symptoms and dust exposure, and between chest symptoms and breaking moldy bottles. Put another way, these nose and throat irritation and chest symptoms were linked to environmental exposures even after taking the impact of differences in psychosocial factors into account. With respect to other symptom complexes studied (eye and skin irritation and somatic symptoms) it appeared that increased job strain (i.e. relatively poorer balance between perceived psychological demands of work and individual control over work tasks) and reduced work satisfaction and poorer communication between management and labour may be more important factors contributing to increased reporting of these symptoms among LDB employees than specific work exposures. It is also possible that the appearance of these symptoms were linked to increased stress associated with a poorer score for these work environment indicators. The data in this study do not favour one explanation over the other. These findings should be interpreted in light of the fact that this study was not specifically designed to address issues related to psychosocial dimensions of work, work stress, and their potential impact on health. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 74 of 76 10 Conclusions 1. As no relationship was demonstrated between operation of glass breaking machines and either symptoms or measured levels of dust, endotoxin, or viable fungi, it is not clear that halting the glass breaking but continuing recycling would reduce exposures or symptoms. 2. There is some evidence that the presence of recycled materials in the stores is associated with an increase in fungal levels. There is stronger evidence that an important contributor to fungal levels was whether or not visually contaminated bottles were being broken in the store (either mechanically or manually). Removal or redesign of the recycling operations in LDB stores may reduce fungal exposures and could have a positive effect on symptoms. 3. There is some evidence that dust exposures in LDB stores is associated with an increase in acute irritation of the nose and throat. The source of the dust is not clear. Results suggest that the dust measured may be a combination of outdoor dust being brought indoors, dust from stocking shelves and dust from the glass breaking operations, but no analyses were carried out to examine the chemical makeup of the dust collected. Improved dust control measures may have a positive effect on these symptoms. 4. Attention to improving the psychosocial dimensions of the work environment may also have a positive impact on some symptoms. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 75 of 76 11 References (1) Midtgard U, Wurtz H, Breum NO, Ebbehoj N, Poulsen OM. Bioaerosol exposure and related health effects in waste collection. Schriftenreihe des Vereins fur Wasser-, Boden-, und Lufthygiene 1999; 104:523-532. (2) Kiviranta H, Tuomainen A, Reiman M, Laitinen S, Nevalainen A, Liesivuori et al. Exposure to airborne microorganisms and volatile organic compounds in different types of waste handling. Annals of Agricultural & Environmental Medicine 1999; 6(1):39-44. (3) Poulsen OM, Breum NO, Ebbehoj N, Hansen AM, Ivens UI, van Lelieveld D et al. Sorting and recycling of domestic waste. Review of occupational health problems and their possible causes. Science of the Total Environment 1995; 168(1):33-56. (4) Jagielo PJ, Thorne PS, Watt JL, Frees KL, Quinn TJ, Schwartz DA. Grain dust and endotoxin inhalation challenges produce similar inflammatory responses in normal subjects. Chest 1996; 110(1):263-270. (5) Wouters IM, Douwes J, Doekes G, Thorne PS, Brunekreef B, Heederik DJ. Increased levels of markers of microbial exposure in homes with indoor storage of organic household waste. Appl Environ Microbiol 2000; 66(2):627-631. (6) Sprince NL, Thorne PS, Popendorf W, Zwerling C, Miller ER, DeKoster.JA. Respiratory symptoms and lung function abnormalities among machine operators in automobile production. Am J Ind Med 1997; 31(4):403-413. (7) American Lung Association. Recommended respiratory diseases questionnaire for use with adults and children in epidemiological research. Am Rev Respir Dis 1978; 118:7-53. (8) Karasek R, Brisson C, Kawakami N, Houtman I, Bongers P, Amick E. The Job Content Questionnaire (JCQ): asn instrument for internationally comparative assessments of psychosocial job characteristics. Journal of Occupational Psychology 1998; 3:322-355. (9) Castellan RM, Olenchock SA, Kinsley KB, Hankinson JL. Inhaled endotoxin and decreased spirometric values. An exposure-response relation for cotton dust. NEJM 1987; 317(10):605-610. (10) American Conference of Governmental and Industrial Hygienists. TLVs and BEIs: Threshold Limit Values for Chemical Substances and Physical Agents. Biological Exposure Indices. Cincinnati: ACGIH, 2000. (11) Health Canada. Indoor Air Quality in Office Buildings: A Technical Guide. 1995. (12) Amick BC, III, Kawachi I, Coakley EH, Lerner D, Levine S, Colditz GA. Relationship of job strain and iso-strain to health status in a cohort of women in the United States. Scand J Work Environ Health 1998; 24(1):54-61. (13) Punnett L. Adjusting for the healthy worker selection effect in cross-sectional studies. Int J Epidemiol 1996; 25(5):1068-1076. (14) Thorn J, Beijer L, Rylander R. Airways inflammation and glucan exposure among household waste collectors. Am J Ind Med 1998; 33(5):463-470. (15) Mandryk J, Alwis KU, Hocking AD. Work-related symptoms and dose-response relationships for personal exposures and pulmonary function among woodworkers. Am J Ind Med 1999; 35(5):481-490. Final Report, August 7, 2001 UBC School of Occupational and Environmental Hygiene Page 76 of 76 12 Appendices Appendix 1 - Forms used in this study Appendix 2 - Detailed exposure sampling protocols Appendix 3 - Definitions and description of variables used Appendix 4 - Individual store results Page 1 of 2 UBC School of Occupational and Environmental Hygiene Bioaerosols, Airborne Particulate Matter and Symptoms in BC Liquor Distribution Branch Stores Summary of Results Why did we do this study? Last summer, the BC Liquor Distribution Branch and the BC Government and Service Employees Union asked UBC to help investigate workplace exposures linked to the use of glass breaking machinery in BC liquor stores and their possible impact on employee health. This study plan was endorsed by both management and the union and by the BC Workers' Compensation Board. What did we do? We tested 36 stores (34 stores chosen at random by UBC and 1 each nominated by the LDB and the BCGEU). Only the UBC researchers knew which stores were selected until the day before the testing. We visited each store twice. Between the two testing visits, the glass breaking machines were shut down for one month in half the stores. In each store, we repeated the same testing on each of the two visits. Dust measurements: We measured dust levels using a filter device clipped to each employee's lapel and worn throughout the work shift. The filter captured glass dust as well as dust from any other sources in the store. Bio-aerosol measurements: We measured endotoxin (from bacteria) and fungal (mould) spores in the air because other studies of recycling workers have found these to be linked to symptoms. Fungal spores and bacteria are commonly found wherever there is contaminated water or organic materials (such as beer and wine residues). Endotoxin was measured from the same dust filter worn by each employee all day. Fungi were measured with devices placed in several locations throughout the store. Each fungal sample only collected air for 5 minutes. Employee interviews: We interviewed each employee on shift during our visits. We used a standard questionnaire to ask about ongoing symptoms and about important parts of each person's health and medical history. We used a second questionnaire to ask about symptoms during the week before the test. We also used a standard questionnaire to measure some psychosocial aspects of the work environment including job strain (which compares the psychological demands of work to the level of individual control over work tasks) and employee-employer communication. Where can you get more information about the study? A detailed technical report describing our results has been provided to LDB management, the BCGEU, and the Workers' Compensation Board. It is also available for reading and downloading from our website at: www.soeh.ubc.ca . (Please turn the page over for information about what we found.). Page 2 of 2 What did we find? Dust and symptoms: Dust levels were low (and below the current WCB exposure limit). Dust levels were highest among employees who spent more time in the back section of the stores. Dust levels were no different when glass machines were operating or not. The dust may be combination of outdoor dust being brought indoors, dust from shelf stocking operations and dust from the glass breaking operations. Higher dust levels were linked to more nose and throat irritation in the past week. Dust levels did not appear to be linked to any of the other symptoms. Endotoxin and symptoms: Endotoxin levels were low. There is no North American exposure limit for endotoxin; there is a newly proposed limit in the Netherlands. The levels we found were below this. None of the symptoms was linked to endotoxin exposure. Fungi and symptoms: Fungal levels were higher than typical levels in an office or residential building. They were highest around broken bottles and near the empties return counter, next highest elsewhere in the warehouse, and lowest at the cashier station. This was true when the glass breaking equipment was operating as well as when it was not operating. The most important factor linked to higher fungal counts was if mouldy bottles were being broken in the store (either in the glass breaking machines or by throwing them into bins). Having uncovered glass bins in the warehouse also contributed to higher fungal levels. More chest symptoms in the past week (chest tightness, wheezing, cough, and breathlessness) were reported in stores where mouldy bottles were being broken on the test day. However, none of the symptoms was linked directly to the fungal measurements. Other findings: In general, LDB employees reported about twice as much chronic tightness in the chest, more nasal irritation, and more eye irritation at work than a similar group of BC Ferry employees. Employees reporting higher levels of job strain, more job dissatisfaction, and poorer workplace communication reported more eye and skin irritation and somatic symptoms. What did we conclude? As none of the exposures or symptoms appeared to be linked to the operation of glass breaking machines, we could not conclude that halting the glass breaking, while continuing recycling, would reduce exposures or symptoms. Based on the links between fungal levels and the presence of recycled materials in the stores in general and on whether or not mouldy bottles were being broken in the stores, we suggested that removal or redesign of the recycling operations may reduce fungal levels and symptoms. We also suggested that improved dust control measures (for dust from all sources) and attention to improving the psychosocial dimensions of the work environment might have a positive effect on some symptoms."@en ; edm:hasType "Report"@en ; edm:isShownAt "10.14288/1.0048227"@en ; dcterms:language "eng"@en ; ns0:peerReviewStatus "Unreviewed"@en ; edm:provider "Vancouver : University of British Columbia Library"@en ; dcterms:rights "All rights reserved"@en ; ns0:scholarLevel "Faculty"@en, "Other"@en ; dcterms:subject "Workplace health"@en ; dcterms:title "Bioaerosols, airborne particulate matter, and symptoms at BC Liquor Distribution stores"@en ; dcterms:type "Text"@en ; ns0:identifierURI "http://hdl.handle.net/2429/882"@en .